Merge pull request #776 from pavlozt/fix/sudo_path

Fix(installer): workaround for systems with secure PATH

Cargo.lock

@@ -2791,7 +2791,7 @@ checksum = "7b2093cf4c8eb1e67749a6762251bc9cd836b6fc171623bd0a9d324d37af2417"
 
 [[package]]
 name = "telemt"
-version = "3.4.8"
+version = "3.4.10"
 dependencies = [
  "aes",
  "anyhow",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "telemt"
-version = "3.4.8"
+version = "3.4.10"
 edition = "2024"
 
 [features]

README.md

@@ -1,6 +1,6 @@
 # Telemt - MTProxy on Rust + Tokio
 
-[![Latest Release](https://img.shields.io/github/v/release/telemt/telemt?color=neon)](https://github.com/telemt/telemt/releases/latest) [![Stars](https://img.shields.io/github/stars/telemt/telemt?style=social)](https://github.com/telemt/telemt/stargazers) [![Forks](https://img.shields.io/github/forks/telemt/telemt?style=social)](https://github.com/telemt/telemt/network/members) [![Telegram](https://img.shields.io/badge/Telegram-Chat-24a1de?logo=telegram&logoColor=24a1de)](https://t.me/telemtrs)
+[![Latest Release](https://img.shields.io/github/v/release/telemt/telemt?color=neon)](https://github.com/telemt/telemt/releases/latest) [![Stars](https://img.shields.io/github/stars/telemt/telemt?style=social)](https://github.com/telemt/telemt/stargazers) [![Forks](https://img.shields.io/github/forks/telemt/telemt?style=social)](https://github.com/telemt/telemt/network/members)
 
 [🇷🇺 README на русском](https://github.com/telemt/telemt/blob/main/README.ru.md)
 
@@ -14,7 +14,7 @@
 
 <p align="center">
   <a href="https://t.me/telemtrs">
-    <img src="/docs/assets/telegram_button.svg" width="150"/>
+    <img src="https://github.com/user-attachments/assets/30b7e7b9-974a-4e3d-aab6-b58a85de4507" width="240"/>
   </a>
 </p>
 
@@ -99,7 +99,7 @@ Monero (XMR) directly:
 8Bk4tZEYPQWSypeD2hrUXG2rKbAKF16GqEN942ZdAP5cFdSqW6h4DwkP5cJMAdszzuPeHeHZPTyjWWFwzeFdjuci3ktfMoB
 ```
 
-All donations go toward infrastructure, development, and research.
+All donations go toward infrastructure, development and research
 
 
 ![telemt_scheme](docs/assets/telemt.png)

docs/Architecture/API/API.md

@@ -178,6 +178,21 @@ Notes:
 | `data_quota_bytes` | `u64` | no | Per-user traffic quota. |
 | `max_unique_ips` | `usize` | no | Per-user unique source IP limit. |
 
+### `access.user_source_deny` via API
+- In current API surface, per-user deny-list is **not** exposed as a dedicated field in `CreateUserRequest` / `PatchUserRequest`.
+- Configure it in `config.toml` under `[access.user_source_deny]` and apply via normal config reload path.
+- Runtime behavior after apply:
+  - auth succeeds for username/secret
+  - source IP is checked against `access.user_source_deny[username]`
+  - on match, handshake is rejected with the same fail-closed outcome as invalid auth
+
+Example config:
+```toml
+[access.user_source_deny]
+alice = ["203.0.113.0/24", "2001:db8:abcd::/48"]
+bob = ["198.51.100.42/32"]
+```
+
 ### `RotateSecretRequest`
 | Field | Type | Required | Description |
 | --- | --- | --- | --- |

docs/Architecture/Fronting-splitting/TLS_FRONT_PROFILE_FIDELITY.en.md

@@ -128,7 +128,48 @@ Recommended for cleaner testing:
 
 Persisted cache artifacts are useful, but they are not required if packet captures already demonstrate the runtime result.
 
-### 4. Capture a direct-origin trace
+### 4. Check TLS-front profile health metrics
+
+If the metrics endpoint is enabled, check the TLS-front profile health before packet-capture validation:
+
+```bash
+curl -s http://127.0.0.1:9999/metrics | grep -E 'telemt_tls_front_profile|telemt_tls_fetch_profile_cache|telemt_tls_front_full_cert'
+```
+
+The profile-health metrics expose the runtime state of configured TLS front domains:
+
+- `telemt_tls_front_profile_domains` shows configured, emitted, and suppressed domain series.
+- `telemt_tls_front_profile_info` shows profile source and feature flags per domain.
+- `telemt_tls_front_profile_age_seconds` shows cached profile age.
+- `telemt_tls_front_profile_app_data_records` shows cached AppData record count.
+- `telemt_tls_front_profile_ticket_records` shows cached ticket-like tail record count.
+- `telemt_tls_front_profile_change_cipher_spec_records` shows cached ChangeCipherSpec count.
+- `telemt_tls_front_profile_app_data_bytes` shows total cached AppData bytes.
+
+Interpretation:
+
+- `source="merged"` or `source="raw"` means real TLS profile data is being used.
+- `source="default"` or `is_default="true"` means the domain currently uses the synthetic default fallback.
+- `has_cert_payload="true"` means certificate payload data is available for TLS emulation.
+- Non-zero AppData/ticket/CCS counters show captured server-flight shape.
+
+Example healthy output:
+
+```text
+telemt_tls_front_profile_domains{status="configured"} 1
+telemt_tls_front_profile_domains{status="emitted"} 1
+telemt_tls_front_profile_domains{status="suppressed"} 0
+telemt_tls_front_profile_info{domain="itunes.apple.com",source="merged",is_default="false",has_cert_info="true",has_cert_payload="true"} 1
+telemt_tls_front_profile_age_seconds{domain="itunes.apple.com"} 20
+telemt_tls_front_profile_app_data_records{domain="itunes.apple.com"} 3
+telemt_tls_front_profile_ticket_records{domain="itunes.apple.com"} 1
+telemt_tls_front_profile_change_cipher_spec_records{domain="itunes.apple.com"} 1
+telemt_tls_front_profile_app_data_bytes{domain="itunes.apple.com"} 5240
+```
+
+These metrics do not prove byte-level origin equivalence. They are an operational health signal that the configured domain is backed by real cached profile data instead of default fallback data.
+
+### 5. Capture a direct-origin trace
 
 From a separate client host, connect directly to the origin:
 
@@ -142,7 +183,7 @@ Capture with:
 sudo tcpdump -i any -w origin-direct.pcap host ORIGIN_IP and port 443
 ```
 
-### 5. Capture a Telemt FakeTLS success-path trace
+### 6. Capture a Telemt FakeTLS success-path trace
 
 Now connect to Telemt with a real Telegram client through an `ee` proxy link that targets the Telemt instance.
 
@@ -154,7 +195,7 @@ Capture with:
 sudo tcpdump -i any -w telemt-emulated.pcap host TELEMT_IP and port 443
 ```
 
-### 6. Decode TLS record structure
+### 7. Decode TLS record structure
 
 Use `tshark` to print record-level structure:
 
@@ -182,7 +223,7 @@ Focus on the server flight after ClientHello:
 - `20` = ChangeCipherSpec
 - `23` = ApplicationData
 
-### 7. Build a comparison table
+### 8. Build a comparison table
 
 A compact table like the following is usually enough:
 

docs/Architecture/Fronting-splitting/TLS_FRONT_PROFILE_FIDELITY.ru.md

@@ -126,9 +126,50 @@ openssl s_client -connect ORIGIN_IP:443 -servername YOUR_DOMAIN </dev/null
 2. Дайте ему получить TLS front profile data для выбранного домена.
 3. Если `tls_front_dir` хранится persistently, убедитесь, что TLS front cache заполнен.
 
-Persisted cache artifacts полезны, но не обязательны, если packet capture уже показывают runtime result.
+Сохранённые артефакты кэша полезны, но не обязательны, если packet capture уже показывает результат в runtime.
 
-### 4. Снять direct-origin trace
+### 4. Проверить метрики состояния TLS-front profile
+
+Если endpoint метрик включён, перед проверкой через packet capture можно быстро проверить состояние TLS-front profile:
+
+```bash
+curl -s http://127.0.0.1:9999/metrics | grep -E 'telemt_tls_front_profile|telemt_tls_fetch_profile_cache|telemt_tls_front_full_cert'
+```
+
+Метрики состояния профиля показывают runtime-состояние настроенных TLS-front доменов:
+
+- `telemt_tls_front_profile_domains` показывает количество настроенных, экспортируемых и скрытых из-за лимита доменов.
+- `telemt_tls_front_profile_info` показывает источник профиля и флаги доступных данных по каждому домену.
+- `telemt_tls_front_profile_age_seconds` показывает возраст закешированного профиля.
+- `telemt_tls_front_profile_app_data_records` показывает количество закешированных AppData records.
+- `telemt_tls_front_profile_ticket_records` показывает количество закешированных ticket-like tail records.
+- `telemt_tls_front_profile_change_cipher_spec_records` показывает закешированное количество ChangeCipherSpec records.
+- `telemt_tls_front_profile_app_data_bytes` показывает общий размер закешированных AppData bytes.
+
+Интерпретация:
+
+- `source="merged"` или `source="raw"` означает, что используются реальные данные TLS-профиля.
+- `source="default"` или `is_default="true"` означает, что домен сейчас работает на synthetic default fallback.
+- `has_cert_payload="true"` означает, что certificate payload доступен для TLS emulation.
+- Ненулевые AppData/ticket/CCS counters показывают захваченную форму server flight.
+
+Пример здорового состояния:
+
+```text
+telemt_tls_front_profile_domains{status="configured"} 1
+telemt_tls_front_profile_domains{status="emitted"} 1
+telemt_tls_front_profile_domains{status="suppressed"} 0
+telemt_tls_front_profile_info{domain="itunes.apple.com",source="merged",is_default="false",has_cert_info="true",has_cert_payload="true"} 1
+telemt_tls_front_profile_age_seconds{domain="itunes.apple.com"} 20
+telemt_tls_front_profile_app_data_records{domain="itunes.apple.com"} 3
+telemt_tls_front_profile_ticket_records{domain="itunes.apple.com"} 1
+telemt_tls_front_profile_change_cipher_spec_records{domain="itunes.apple.com"} 1
+telemt_tls_front_profile_app_data_bytes{domain="itunes.apple.com"} 5240
+```
+
+Эти метрики не доказывают побайтную эквивалентность с origin. Это эксплуатационный сигнал состояния: настроенный домен действительно основан на реальных закешированных данных профиля, а не на default fallback.
+
+### 5. Снять direct-origin trace
 
 С отдельной клиентской машины подключитесь напрямую к origin:
 
@@ -142,7 +183,7 @@ Capture:
 sudo tcpdump -i any -w origin-direct.pcap host ORIGIN_IP and port 443
 ```
 
-### 5. Снять Telemt FakeTLS success-path trace
+### 6. Снять Telemt FakeTLS success-path trace
 
 Теперь подключитесь к Telemt через реальный Telegram client с `ee` proxy link, который указывает на Telemt instance.
 
@@ -154,7 +195,7 @@ Capture:
 sudo tcpdump -i any -w telemt-emulated.pcap host TELEMT_IP and port 443
 ```
 
-### 6. Декодировать структуру TLS records
+### 7. Декодировать структуру TLS records
 
 Используйте `tshark`, чтобы вывести record-level structure:
 
@@ -182,7 +223,7 @@ tshark -r telemt-emulated.pcap -Y "tls.record" -T fields \
 - `20` = ChangeCipherSpec
 - `23` = ApplicationData
 
-### 7. Собрать сравнительную таблицу
+### 8. Собрать сравнительную таблицу
 
 Обычно достаточно короткой таблицы такого вида:
 

docs/Config_params/CONFIG_PARAMS.en.md

@@ -162,6 +162,8 @@ This document lists all configuration keys accepted by `config.toml`.
 | [`log_level`](#log_level) | `"debug"`, `"verbose"`, `"normal"`, or `"silent"` | `"normal"` |
 | [`disable_colors`](#disable_colors) | `bool` | `false` |
 | [`me_socks_kdf_policy`](#me_socks_kdf_policy) | `"strict"` or `"compat"` | `"strict"` |
+| [`me_route_backpressure_enabled`](#me_route_backpressure_enabled) | `bool` | `false` |
+| [`me_route_fairshare_enabled`](#me_route_fairshare_enabled) | `bool` | `false` |
 | [`me_route_backpressure_base_timeout_ms`](#me_route_backpressure_base_timeout_ms) | `u64` | `25` |
 | [`me_route_backpressure_high_timeout_ms`](#me_route_backpressure_high_timeout_ms) | `u64` | `120` |
 | [`me_route_backpressure_high_watermark_pct`](#me_route_backpressure_high_watermark_pct) | `u8` | `80` |
@@ -975,6 +977,24 @@ This document lists all configuration keys accepted by `config.toml`.
     [general]
     me_socks_kdf_policy = "strict"
     ```
+## me_route_backpressure_enabled
+  - **Constraints / validation**: `bool`.
+  - **Description**: Enables channel-pressure-aware route send timeouts.
+  - **Example**:
+
+    ```toml
+    [general]
+    me_route_backpressure_enabled = false
+    ```
+## me_route_fairshare_enabled
+  - **Constraints / validation**: `bool`.
+  - **Description**: Enables fair-share routing admission across writer workers.
+  - **Example**:
+
+    ```toml
+    [general]
+    me_route_fairshare_enabled = false
+    ```
 ## me_route_backpressure_base_timeout_ms
   - **Constraints / validation**: Must be within `1..=5000` (milliseconds).
   - **Description**: Base backpressure timeout in milliseconds for ME route-channel send.
@@ -1753,6 +1773,7 @@ This document lists all configuration keys accepted by `config.toml`.
 | [`metrics_whitelist`](#metrics_whitelist) | `IpNetwork[]` | `["127.0.0.1/32", "::1/128"]` |
 | [`max_connections`](#max_connections) | `u32` | `10000` |
 | [`accept_permit_timeout_ms`](#accept_permit_timeout_ms) | `u64` | `250` |
+| [`listen_backlog`](#listen_backlog) | `u32` | `1024` |
 
 ## port
   - **Constraints / validation**: `u16`.
@@ -1763,6 +1784,15 @@ This document lists all configuration keys accepted by `config.toml`.
     [server]
     port = 443
     ```
+## listen_backlog
+  - **Constraints / validation**: `u32`. `0` uses the OS default backlog behavior.
+  - **Description**: Listen backlog passed to `listen(2)` for TCP sockets.
+  - **Example**:
+
+    ```toml
+    [server]
+    listen_backlog = 1024
+    ```
 ## listen_addr_ipv4
   - **Constraints / validation**: `String` (optional). When set, must be a valid IPv4 address string.
   - **Description**: IPv4 bind address for TCP listener (omit this key to disable IPv4 bind).
@@ -2005,6 +2035,7 @@ Note: This section also accepts the legacy alias `[server.admin_api]` (same sche
 | [`runtime_edge_top_n`](#runtime_edge_top_n) | `usize` | `10` |
 | [`runtime_edge_events_capacity`](#runtime_edge_events_capacity) | `usize` | `256` |
 | [`read_only`](#read_only) | `bool` | `false` |
+| [`gray_action`](#gray_action) | `"drop"`, `"api"`, or `"200"` | `"drop"` |
 
 ## enabled
   - **Constraints / validation**: `bool`.
@@ -2015,6 +2046,15 @@ Note: This section also accepts the legacy alias `[server.admin_api]` (same sche
     [server.api]
     enabled = true
     ```
+## gray_action
+  - **Constraints / validation**: `"drop"`, `"api"`, or `"200"`.
+  - **Description**: API response policy for gray/limited states: drop request, serve normal API response, or force `200 OK`.
+  - **Example**:
+
+    ```toml
+    [server.api]
+    gray_action = "drop"
+    ```
 ## listen
   - **Constraints / validation**: `String`. Must be in `IP:PORT` format.
   - **Description**: API bind address in `IP:PORT` format.
@@ -2207,6 +2247,15 @@ Note: This section also accepts the legacy alias `[server.admin_api]` (same sche
     [timeouts]
     client_handshake = 30
     ```
+## client_first_byte_idle_secs
+  - **Constraints / validation**: `u64` (seconds). `0` disables first-byte idle enforcement.
+  - **Description**: Maximum idle time to wait for the first client payload byte after session setup.
+  - **Example**:
+
+    ```toml
+    [timeouts]
+    client_first_byte_idle_secs = 300
+    ```
 ## relay_idle_policy_v2_enabled
   - **Constraints / validation**: `bool`.
   - **Description**: Enables soft/hard middle-relay client idle policy.
@@ -2311,6 +2360,7 @@ Note: This section also accepts the legacy alias `[server.admin_api]` (same sche
 | [`server_hello_delay_max_ms`](#server_hello_delay_max_ms) | `u64` | `0` |
 | [`tls_new_session_tickets`](#tls_new_session_tickets) | `u8` | `0` |
 | [`tls_full_cert_ttl_secs`](#tls_full_cert_ttl_secs) | `u64` | `90` |
+| [`serverhello_compact`](#serverhello_compact) | `bool` | `false` |
 | [`alpn_enforce`](#alpn_enforce) | `bool` | `true` |
 | [`mask_proxy_protocol`](#mask_proxy_protocol) | `u8` | `0` |
 | [`mask_shape_hardening`](#mask_shape_hardening) | `bool` | `true` |
@@ -2488,6 +2538,15 @@ Note: This section also accepts the legacy alias `[server.admin_api]` (same sche
     [censorship]
     tls_full_cert_ttl_secs = 90
     ```
+## serverhello_compact
+  - **Constraints / validation**: `bool`.
+  - **Description**: Enables compact ServerHello/Fake-TLS profile to reduce response-size signature.
+  - **Example**:
+
+    ```toml
+    [censorship]
+    serverhello_compact = false
+    ```
 ## alpn_enforce
   - **Constraints / validation**: `bool`.
   - **Description**: Enforces ALPN echo behavior based on client preference.
@@ -2827,9 +2886,12 @@ If your backend or network is very bandwidth-constrained, reduce cap first. If p
 | [`user_max_unique_ips_global_each`](#user_max_unique_ips_global_each) | `usize` | `0` |
 | [`user_max_unique_ips_mode`](#user_max_unique_ips_mode) | `"active_window"`, `"time_window"`, or `"combined"` | `"active_window"` |
 | [`user_max_unique_ips_window_secs`](#user_max_unique_ips_window_secs) | `u64` | `30` |
+| [`user_source_deny`](#user_source_deny) | `Map<String, IpNetwork[]>` | `{}` |
 | [`replay_check_len`](#replay_check_len) | `usize` | `65536` |
 | [`replay_window_secs`](#replay_window_secs) | `u64` | `120` |
 | [`ignore_time_skew`](#ignore_time_skew) | `bool` | `false` |
+| [`user_rate_limits`](#user_rate_limits) | `Map<String, RateLimitBps>` | `{}` |
+| [`cidr_rate_limits`](#cidr_rate_limits) | `Map<IpNetwork, RateLimitBps>` | `{}` |
 
 ## users
   - **Constraints / validation**: Must not be empty (at least one user must exist). Each value must be **exactly 32 hex characters**.
@@ -2929,6 +2991,20 @@ If your backend or network is very bandwidth-constrained, reduce cap first. If p
     [access]
     user_max_unique_ips_window_secs = 30
     ```
+## user_source_deny
+  - **Constraints / validation**: Table `username -> IpNetwork[]`. Each network must parse as CIDR (for example `203.0.113.0/24` or `2001:db8::/32`).
+  - **Description**: Per-user source IP/CIDR deny-list applied **after successful auth** in TLS and MTProto handshake paths. A matched source IP is rejected via the same fail-closed path as invalid auth.
+  - **Example**:
+
+    ```toml
+    [access.user_source_deny]
+    alice = ["203.0.113.0/24", "2001:db8:abcd::/48"]
+    bob = ["198.51.100.42/32"]
+    ```
+
+  - **How it works (quick check)**:
+    - connection from user `alice` and source `203.0.113.55` -> rejected (matches `203.0.113.0/24`)
+    - connection from user `alice` and source `198.51.100.10` -> allowed by this rule set (no match)
 ## replay_check_len
   - **Constraints / validation**: `usize`.
   - **Description**: Replay-protection storage length (number of entries tracked for duplicate detection).
@@ -2958,6 +3034,24 @@ If your backend or network is very bandwidth-constrained, reduce cap first. If p
     ```
 
 
+## user_rate_limits
+  - **Constraints / validation**: Table `username -> { up_bps, down_bps }`. At least one direction must be non-zero.
+  - **Description**: Per-user bandwidth caps in bytes/sec for upload (`up_bps`) and download (`down_bps`).
+  - **Example**:
+
+    ```toml
+    [access.user_rate_limits]
+    alice = { up_bps = 1048576, down_bps = 2097152 }
+    ```
+## cidr_rate_limits
+  - **Constraints / validation**: Table `CIDR -> { up_bps, down_bps }`. CIDR must parse as `IpNetwork`; at least one direction must be non-zero.
+  - **Description**: Source-subnet bandwidth caps applied alongside per-user limits.
+  - **Example**:
+
+    ```toml
+    [access.cidr_rate_limits]
+    "203.0.113.0/24" = { up_bps = 0, down_bps = 1048576 }
+    ```
 # [[upstreams]]
 
 

docs/Config_params/CONFIG_PARAMS.ru.md

@@ -162,6 +162,8 @@
 | [`log_level`](#log_level) | `"debug"`, `"verbose"`, `"normal"`, or `"silent"` | `"normal"` |
 | [`disable_colors`](#disable_colors) | `bool` | `false` |
 | [`me_socks_kdf_policy`](#me_socks_kdf_policy) | `"strict"` or `"compat"` | `"strict"` |
+| [`me_route_backpressure_enabled`](#me_route_backpressure_enabled) | `bool` | `false` |
+| [`me_route_fairshare_enabled`](#me_route_fairshare_enabled) | `bool` | `false` |
 | [`me_route_backpressure_base_timeout_ms`](#me_route_backpressure_base_timeout_ms) | `u64` | `25` |
 | [`me_route_backpressure_high_timeout_ms`](#me_route_backpressure_high_timeout_ms) | `u64` | `120` |
 | [`me_route_backpressure_high_watermark_pct`](#me_route_backpressure_high_watermark_pct) | `u8` | `80` |
@@ -975,6 +977,24 @@
     [general]
     me_socks_kdf_policy = "strict"
     ```
+## me_route_backpressure_enabled
+  - **Ограничения / валидация**: `bool`.
+  - **Описание**: Включает адаптивные таймауты записи маршрута в зависимости от заполнения канала.
+  - **Example**:
+
+    ```toml
+    [general]
+    me_route_backpressure_enabled = false
+    ```
+## me_route_fairshare_enabled
+  - **Ограничения / валидация**: `bool`.
+  - **Описание**: Включает справедливое распределение нагрузки маршрутизации между writer-потоками.
+  - **Example**:
+
+    ```toml
+    [general]
+    me_route_fairshare_enabled = false
+    ```
 ## me_route_backpressure_base_timeout_ms
   - **Ограничения / валидация**: Должно быть в пределах `1..=5000` (миллисекунд).
   - **Описание**: Базовый таймаут (в миллисекундах) ожидания при режиме **backpressure** (ситуация, при которой данные обрабатываются медленне, чем получаются) для отправки через ME route-channel.
@@ -1755,6 +1775,7 @@
 | [`metrics_whitelist`](#metrics_whitelist) | `IpNetwork[]` | `["127.0.0.1/32", "::1/128"]` |
 | [`max_connections`](#max_connections) | `u32` | `10000` |
 | [`accept_permit_timeout_ms`](#accept_permit_timeout_ms) | `u64` | `250` |
+| [`listen_backlog`](#listen_backlog) | `u32` | `1024` |
 
 ## port
   - **Ограничения / валидация**: `u16`.
@@ -1765,6 +1786,15 @@
     [server]
     port = 443
     ```
+## listen_backlog
+  - **Ограничения / валидация**: `u32`. `0` использует системный backlog по умолчанию.
+  - **Описание**: Значение backlog, передаваемое в `listen(2)` для TCP-сокетов.
+  - **Example**:
+
+    ```toml
+    [server]
+    listen_backlog = 1024
+    ```
 ## listen_addr_ipv4
   - **Ограничения / валидация**: `String` (необязательный параметр). Если задан, должен содержать валидный IPv4-адрес в формате строки.
   - **Описание**: Прослушиваемый адрес в формате IPv4 (не задавайте этот параметр, если необходимо отключить прослушивание по IPv4).
@@ -2011,6 +2041,7 @@
 | [`runtime_edge_top_n`](#runtime_edge_top_n) | `usize` | `10` |
 | [`runtime_edge_events_capacity`](#runtime_edge_events_capacity) | `usize` | `256` |
 | [`read_only`](#read_only) | `bool` | `false` |
+| [`gray_action`](#gray_action) | `"drop"`, `"api"`, or `"200"` | `"drop"` |
 
 ## enabled
   - **Ограничения / валидация**: `bool`.
@@ -2021,6 +2052,15 @@
     [server.api]
     enabled = true
     ```
+## gray_action
+  - **Ограничения / валидация**: `"drop"`, `"api"` или `"200"`.
+  - **Описание**: Политика ответа API в «серых» (ограниченных) состояниях: сброс, обычный API-ответ, либо `200 OK`.
+  - **Example**:
+
+    ```toml
+    [server.api]
+    gray_action = "drop"
+    ```
 ## listen
   - **Ограничения / валидация**: `String`. Должно быть в формате `IP:PORT`.
   - **Описание**: Адрес биндинга API в формате `IP:PORT`.
@@ -2213,6 +2253,15 @@
     [timeouts]
     client_handshake = 30
     ```
+## client_first_byte_idle_secs
+  - **Ограничения / валидация**: `u64` (секунды). `0` отключает проверку простоя до первого байта.
+  - **Описание**: Максимальное время ожидания первого байта полезной нагрузки от клиента после установления сессии.
+  - **Example**:
+
+    ```toml
+    [timeouts]
+    client_first_byte_idle_secs = 300
+    ```
 ## relay_idle_policy_v2_enabled
   - **Ограничения / валидация**: `bool`.
   - **Описание**: Включает политику простоя клиента для промежуточного узла.
@@ -2317,6 +2366,7 @@
 | [`server_hello_delay_max_ms`](#server_hello_delay_max_ms) | `u64` | `0` |
 | [`tls_new_session_tickets`](#tls_new_session_tickets) | `u8` | `0` |
 | [`tls_full_cert_ttl_secs`](#tls_full_cert_ttl_secs) | `u64` | `90` |
+| [`serverhello_compact`](#serverhello_compact) | `bool` | `false` |
 | [`alpn_enforce`](#alpn_enforce) | `bool` | `true` |
 | [`mask_proxy_protocol`](#mask_proxy_protocol) | `u8` | `0` |
 | [`mask_shape_hardening`](#mask_shape_hardening) | `bool` | `true` |
@@ -2493,6 +2543,15 @@
     [censorship]
     tls_full_cert_ttl_secs = 90
     ```
+## serverhello_compact
+  - **Ограничения / валидация**: `bool`.
+  - **Описание**: Включает компактный профиль ServerHello/Fake-TLS для снижения сигнатуры размера ответа.
+  - **Example**:
+
+    ```toml
+    [censorship]
+    serverhello_compact = false
+    ```
 ## alpn_enforce
   - **Ограничения / валидация**: `bool`.
   - **Описание**: Принудительно изменяет поведение возврата ALPN в соответствии с предпочтениями клиента.
@@ -2837,6 +2896,8 @@
 | [`replay_check_len`](#replay_check_len) | `usize` | `65536` |
 | [`replay_window_secs`](#replay_window_secs) | `u64` | `120` |
 | [`ignore_time_skew`](#ignore_time_skew) | `bool` | `false` |
+| [`user_rate_limits`](#user_rate_limits) | `Map<String, RateLimitBps>` | `{}` |
+| [`cidr_rate_limits`](#cidr_rate_limits) | `Map<IpNetwork, RateLimitBps>` | `{}` |
 
 ## users
   - **Ограничения / валидация**: Не должно быть пустым (должен существовать хотя бы один пользователь). Каждое значение должно состоять **ровно из 32 шестнадцатеричных символов**.
@@ -2965,6 +3026,24 @@
     ```
 
 
+## user_rate_limits
+  - **Ограничения / валидация**: Таблица `username -> { up_bps, down_bps }`. Должно быть ненулевое значение хотя бы в одном направлении.
+  - **Описание**: Персональные лимиты скорости по пользователям в байтах/сек для отправки (`up_bps`) и получения (`down_bps`).
+  - **Example**:
+
+    ```toml
+    [access.user_rate_limits]
+    alice = { up_bps = 1048576, down_bps = 2097152 }
+    ```
+## cidr_rate_limits
+  - **Ограничения / валидация**: Таблица `CIDR -> { up_bps, down_bps }`. CIDR должен корректно разбираться как `IpNetwork`; хотя бы одно направление должно быть ненулевым.
+  - **Описание**: Лимиты скорости для подсетей источников, применяются поверх пользовательских ограничений.
+  - **Example**:
+
+    ```toml
+    [access.cidr_rate_limits]
+    "203.0.113.0/24" = { up_bps = 0, down_bps = 1048576 }
+    ```
 # [[upstreams]]
 
 

docs/Quick_start/QUICK_START_GUIDE.ru.md

@@ -164,7 +164,7 @@ tls_front_dir = "tlsfront"   # Директория кэша для эмуляц
 hello = "00000000000000000000000000000000"
 ```
 
-Затем нажмите Ctrl+S -> Ctrl+X, чтобы сохранить
+Затем нажмите Ctrl+O -> Ctrl+X, чтобы сохранить
 
 > [!WARNING]
 > Замените значение параметра `hello` на значение, которое вы получили в пункте 0.  

install.sh

@@ -27,6 +27,8 @@ ACTION="install"
 TARGET_VERSION="${VERSION:-latest}"
 LANG_CHOICE="en"
 
+PATH="${PATH}:/usr/sbin:/sbin"
+
 set_language() {
     case "$1" in
         ru)
@@ -102,6 +104,7 @@ set_language() {
             L_OUT_SUCC_H="УСТАНОВКА УСПЕШНО ЗАВЕРШЕНА"
             L_OUT_UNINST_H="УДАЛЕНИЕ ЗАВЕРШЕНО"
             L_OUT_LINK="Ваша ссылка для подключения к Telegram Proxy:\n"
+            L_ERR_INCORR_ROOT_LOGIN="Используйте 'su -' или 'sudo -i' для входа под пользователем root"
             ;;
         *)
             L_ERR_DOMAIN_REQ="requires a domain argument."
@@ -176,6 +179,7 @@ set_language() {
             L_OUT_SUCC_H="INSTALLATION SUCCESS"
             L_OUT_UNINST_H="UNINSTALLATION COMPLETE"
             L_OUT_LINK="Your Telegram Proxy connection link:\n"
+            L_ERR_INCORR_ROOT_LOGIN="Use 'su -' or 'sudo -i' to login under root"
             ;;
     esac
 }
@@ -388,6 +392,9 @@ verify_common() {
 
     if [ "$(id -u)" -eq 0 ]; then
         SUDO=""
+        if [ "$(id -u)" -ne 0 ]; then
+            die "$L_ERR_INCORR_ROOT_LOGIN"
+        fi
     else
         command -v sudo >/dev/null 2>&1 || die "$L_ERR_ROOT"
         SUDO="sudo"

src/api/config_store.rs

@@ -82,6 +82,7 @@ pub(super) async fn load_config_from_disk(config_path: &Path) -> Result<ProxyCon
         .map_err(|e| ApiFailure::internal(format!("failed to load config: {}", e)))
 }
 
+#[allow(dead_code)]
 pub(super) async fn save_config_to_disk(
     config_path: &Path,
     cfg: &ProxyConfig,
@@ -106,6 +107,12 @@ pub(super) async fn save_access_sections_to_disk(
         if applied.contains(section) {
             continue;
         }
+        if find_toml_table_bounds(&content, section.table_name()).is_none()
+            && access_section_is_empty(cfg, *section)
+        {
+            applied.push(*section);
+            continue;
+        }
         let rendered = render_access_section(cfg, *section)?;
         content = upsert_toml_table(&content, section.table_name(), &rendered);
         applied.push(*section);
@@ -183,6 +190,17 @@ fn render_access_section(cfg: &ProxyConfig, section: AccessSection) -> Result<St
     Ok(out)
 }
 
+fn access_section_is_empty(cfg: &ProxyConfig, section: AccessSection) -> bool {
+    match section {
+        AccessSection::Users => cfg.access.users.is_empty(),
+        AccessSection::UserAdTags => cfg.access.user_ad_tags.is_empty(),
+        AccessSection::UserMaxTcpConns => cfg.access.user_max_tcp_conns.is_empty(),
+        AccessSection::UserExpirations => cfg.access.user_expirations.is_empty(),
+        AccessSection::UserDataQuota => cfg.access.user_data_quota.is_empty(),
+        AccessSection::UserMaxUniqueIps => cfg.access.user_max_unique_ips.is_empty(),
+    }
+}
+
 fn serialize_table_body<T: Serialize>(value: &T) -> Result<String, ApiFailure> {
     toml::to_string(value)
         .map_err(|e| ApiFailure::internal(format!("failed to serialize access section: {}", e)))

src/api/mod.rs

@@ -43,7 +43,7 @@ use events::ApiEventStore;
 use http_utils::{error_response, read_json, read_optional_json, success_response};
 use model::{
     ApiFailure, ClassCount, CreateUserRequest, DeleteUserResponse, HealthData, HealthReadyData,
-    PatchUserRequest, RotateSecretRequest, SummaryData, UserActiveIps,
+    PatchUserRequest, ResetUserQuotaResponse, RotateSecretRequest, SummaryData, UserActiveIps,
 };
 use runtime_edge::{
     EdgeConnectionsCacheEntry, build_runtime_connections_summary_data,
@@ -80,6 +80,7 @@ pub(super) struct ApiShared {
     pub(super) me_pool: Arc<RwLock<Option<Arc<MePool>>>>,
     pub(super) upstream_manager: Arc<UpstreamManager>,
     pub(super) config_path: PathBuf,
+    pub(super) quota_state_path: PathBuf,
     pub(super) detected_ips_rx: watch::Receiver<(Option<IpAddr>, Option<IpAddr>)>,
     pub(super) mutation_lock: Arc<Mutex<()>>,
     pub(super) minimal_cache: Arc<Mutex<Option<MinimalCacheEntry>>>,
@@ -112,6 +113,7 @@ pub async fn serve(
     config_rx: watch::Receiver<Arc<ProxyConfig>>,
     admission_rx: watch::Receiver<bool>,
     config_path: PathBuf,
+    quota_state_path: PathBuf,
     detected_ips_rx: watch::Receiver<(Option<IpAddr>, Option<IpAddr>)>,
     process_started_at_epoch_secs: u64,
     startup_tracker: Arc<StartupTracker>,
@@ -143,6 +145,7 @@ pub async fn serve(
         me_pool,
         upstream_manager,
         config_path,
+        quota_state_path,
         detected_ips_rx,
         mutation_lock: Arc::new(Mutex::new(())),
         minimal_cache: Arc::new(Mutex::new(None)),
@@ -491,6 +494,56 @@ async fn handle(
                 Ok(success_response(status, data, revision))
             }
             _ => {
+                if method == Method::POST
+                    && let Some(user) = normalized_path
+                        .strip_prefix("/v1/users/")
+                        .and_then(|path| path.strip_suffix("/reset-quota"))
+                    && !user.is_empty()
+                    && !user.contains('/')
+                {
+                    if api_cfg.read_only {
+                        return Ok(error_response(
+                            request_id,
+                            ApiFailure::new(
+                                StatusCode::FORBIDDEN,
+                                "read_only",
+                                "API runs in read-only mode",
+                            ),
+                        ));
+                    }
+                    let snapshot = match crate::quota_state::reset_user_quota(
+                        &shared.quota_state_path,
+                        shared.stats.as_ref(),
+                        user,
+                    )
+                    .await
+                    {
+                        Ok(snapshot) => snapshot,
+                        Err(error) => {
+                            shared.runtime_events.record(
+                                "api.user.reset_quota.failed",
+                                format!("username={} error={}", user, error),
+                            );
+                            return Err(ApiFailure::internal(format!(
+                                "Failed to reset user quota: {}",
+                                error
+                            )));
+                        }
+                    };
+                    shared
+                        .runtime_events
+                        .record("api.user.reset_quota.ok", format!("username={}", user));
+                    let revision = current_revision(&shared.config_path).await?;
+                    return Ok(success_response(
+                        StatusCode::OK,
+                        ResetUserQuotaResponse {
+                            username: user.to_string(),
+                            used_bytes: snapshot.used_bytes,
+                            last_reset_epoch_secs: snapshot.last_reset_epoch_secs,
+                        },
+                        revision,
+                    ));
+                }
                 if let Some(user) = normalized_path.strip_prefix("/v1/users/")
                     && !user.is_empty()
                     && !user.contains('/')

src/api/model.rs

@@ -456,6 +456,13 @@ pub(super) struct UserLinks {
     pub(super) classic: Vec<String>,
     pub(super) secure: Vec<String>,
     pub(super) tls: Vec<String>,
+    pub(super) tls_domains: Vec<TlsDomainLink>,
+}
+
+#[derive(Serialize)]
+pub(super) struct TlsDomainLink {
+    pub(super) domain: String,
+    pub(super) link: String,
 }
 
 #[derive(Serialize)]
@@ -494,6 +501,13 @@ pub(super) struct DeleteUserResponse {
     pub(super) in_runtime: bool,
 }
 
+#[derive(Serialize)]
+pub(super) struct ResetUserQuotaResponse {
+    pub(super) username: String,
+    pub(super) used_bytes: u64,
+    pub(super) last_reset_epoch_secs: u64,
+}
+
 #[derive(Deserialize)]
 pub(super) struct CreateUserRequest {
     pub(super) username: String,

src/api/users.rs

@@ -8,12 +8,12 @@ use crate::stats::Stats;
 
 use super::ApiShared;
 use super::config_store::{
-    AccessSection, ensure_expected_revision, load_config_from_disk, save_access_sections_to_disk,
-    save_config_to_disk,
+    AccessSection, current_revision, ensure_expected_revision, load_config_from_disk,
+    save_access_sections_to_disk,
 };
 use super::model::{
     ApiFailure, CreateUserRequest, CreateUserResponse, PatchUserRequest, RotateSecretRequest,
-    UserInfo, UserLinks, is_valid_ad_tag, is_valid_user_secret, is_valid_username,
+    TlsDomainLink, UserInfo, UserLinks, is_valid_ad_tag, is_valid_user_secret, is_valid_username,
     parse_optional_expiration, parse_patch_expiration, random_user_secret,
 };
 use super::patch::Patch;
@@ -176,6 +176,13 @@ pub(super) async fn patch_user(
     expected_revision: Option<String>,
     shared: &ApiShared,
 ) -> Result<(UserInfo, String), ApiFailure> {
+    let touches_users = body.secret.is_some();
+    let touches_user_ad_tags = !matches!(&body.user_ad_tag, Patch::Unchanged);
+    let touches_user_max_tcp_conns = !matches!(&body.max_tcp_conns, Patch::Unchanged);
+    let touches_user_expirations = !matches!(&body.expiration_rfc3339, Patch::Unchanged);
+    let touches_user_data_quota = !matches!(&body.data_quota_bytes, Patch::Unchanged);
+    let touches_user_max_unique_ips = !matches!(&body.max_unique_ips, Patch::Unchanged);
+
     if let Some(secret) = body.secret.as_ref()
         && !is_valid_user_secret(secret)
     {
@@ -265,7 +272,31 @@ pub(super) async fn patch_user(
     cfg.validate()
         .map_err(|e| ApiFailure::bad_request(format!("config validation failed: {}", e)))?;
 
-    let revision = save_config_to_disk(&shared.config_path, &cfg).await?;
+    let mut touched_sections = Vec::new();
+    if touches_users {
+        touched_sections.push(AccessSection::Users);
+    }
+    if touches_user_ad_tags {
+        touched_sections.push(AccessSection::UserAdTags);
+    }
+    if touches_user_max_tcp_conns {
+        touched_sections.push(AccessSection::UserMaxTcpConns);
+    }
+    if touches_user_expirations {
+        touched_sections.push(AccessSection::UserExpirations);
+    }
+    if touches_user_data_quota {
+        touched_sections.push(AccessSection::UserDataQuota);
+    }
+    if touches_user_max_unique_ips {
+        touched_sections.push(AccessSection::UserMaxUniqueIps);
+    }
+
+    let revision = if touched_sections.is_empty() {
+        current_revision(&shared.config_path).await?
+    } else {
+        save_access_sections_to_disk(&shared.config_path, &cfg, &touched_sections).await?
+    };
     drop(_guard);
     match max_unique_ips_change {
         Some(Some(limit)) => shared.ip_tracker.set_user_limit(user, limit).await,
@@ -438,6 +469,7 @@ pub(super) async fn users_from_config(
                 classic: Vec::new(),
                 secure: Vec::new(),
                 tls: Vec::new(),
+                tls_domains: Vec::new(),
             });
         users.push(UserInfo {
             in_runtime: runtime_cfg
@@ -492,10 +524,12 @@ fn build_user_links(
         .public_port
         .unwrap_or(resolve_default_link_port(cfg));
     let tls_domains = resolve_tls_domains(cfg);
+    let extra_tls_domains = resolve_extra_tls_domains(cfg);
 
     let mut classic = Vec::new();
     let mut secure = Vec::new();
     let mut tls = Vec::new();
+    let mut tls_domain_links = Vec::new();
 
     for host in &hosts {
         if cfg.general.modes.classic {
@@ -518,6 +552,17 @@ fn build_user_links(
                     host, port, secret, domain_hex
                 ));
             }
+            for domain in &extra_tls_domains {
+                let domain_hex = hex::encode(domain);
+                let link = format!(
+                    "tg://proxy?server={}&port={}&secret=ee{}{}",
+                    host, port, secret, domain_hex
+                );
+                tls_domain_links.push(TlsDomainLink {
+                    domain: (*domain).to_string(),
+                    link,
+                });
+            }
         }
     }
 
@@ -525,6 +570,7 @@ fn build_user_links(
         classic,
         secure,
         tls,
+        tls_domains: tls_domain_links,
     }
 }
 
@@ -641,6 +687,19 @@ fn resolve_tls_domains(cfg: &ProxyConfig) -> Vec<&str> {
     domains
 }
 
+fn resolve_extra_tls_domains(cfg: &ProxyConfig) -> Vec<&str> {
+    let mut domains = Vec::with_capacity(cfg.censorship.tls_domains.len());
+    let primary = cfg.censorship.tls_domain.as_str();
+    for domain in &cfg.censorship.tls_domains {
+        let value = domain.as_str();
+        if value.is_empty() || value == primary || domains.contains(&value) {
+            continue;
+        }
+        domains.push(value);
+    }
+    domains
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -730,4 +789,80 @@ mod tests {
         assert!(alice.in_runtime);
         assert!(!bob.in_runtime);
     }
+
+    #[tokio::test]
+    async fn users_from_config_returns_tls_link_for_each_tls_domain() {
+        let mut cfg = ProxyConfig::default();
+        cfg.access.users.insert(
+            "alice".to_string(),
+            "0123456789abcdef0123456789abcdef".to_string(),
+        );
+        cfg.general.modes.classic = false;
+        cfg.general.modes.secure = false;
+        cfg.general.modes.tls = true;
+        cfg.general.links.public_host = Some("proxy.example.net".to_string());
+        cfg.general.links.public_port = Some(443);
+        cfg.censorship.tls_domain = "front-a.example.com".to_string();
+        cfg.censorship.tls_domains = vec![
+            "front-b.example.com".to_string(),
+            "front-c.example.com".to_string(),
+            "front-b.example.com".to_string(),
+            "front-a.example.com".to_string(),
+        ];
+
+        let stats = Stats::new();
+        let tracker = UserIpTracker::new();
+        let users = users_from_config(&cfg, &stats, &tracker, None, None, None).await;
+        let alice = users
+            .iter()
+            .find(|entry| entry.username == "alice")
+            .expect("alice must be present");
+
+        assert_eq!(alice.links.tls.len(), 3);
+        assert!(
+            alice
+                .links
+                .tls
+                .iter()
+                .any(|link| link.ends_with(&hex::encode("front-a.example.com")))
+        );
+        assert!(
+            alice
+                .links
+                .tls
+                .iter()
+                .any(|link| link.ends_with(&hex::encode("front-b.example.com")))
+        );
+        assert!(
+            alice
+                .links
+                .tls
+                .iter()
+                .any(|link| link.ends_with(&hex::encode("front-c.example.com")))
+        );
+        assert_eq!(alice.links.tls_domains.len(), 2);
+        assert!(
+            alice
+                .links
+                .tls_domains
+                .iter()
+                .any(|entry| entry.domain == "front-b.example.com"
+                    && entry.link.ends_with(&hex::encode("front-b.example.com")))
+        );
+        assert!(
+            alice
+                .links
+                .tls_domains
+                .iter()
+                .any(|entry| entry.domain == "front-c.example.com"
+                    && entry.link.ends_with(&hex::encode("front-c.example.com")))
+        );
+        assert!(
+            !alice
+                .links
+                .tls_domains
+                .iter()
+                .any(|entry| entry.domain == "front-a.example.com")
+        );
+    }
 }

src/config/defaults.rs

@@ -102,7 +102,7 @@ pub(crate) fn default_fake_cert_len() -> usize {
 }
 
 pub(crate) fn default_tls_front_dir() -> String {
-    "/etc/telemt/tlsfront".to_string()
+    "tlsfront".to_string()
 }
 
 pub(crate) fn default_replay_check_len() -> usize {
@@ -568,7 +568,7 @@ pub(crate) fn default_beobachten_flush_secs() -> u64 {
 }
 
 pub(crate) fn default_beobachten_file() -> String {
-    "/etc/telemt/beobachten.txt".to_string()
+    "beobachten.txt".to_string()
 }
 
 pub(crate) fn default_tls_new_session_tickets() -> u8 {

src/config/load.rs

@@ -23,6 +23,667 @@ const MAX_ME_C2ME_CHANNEL_CAPACITY: usize = 8_192;
 const MIN_MAX_CLIENT_FRAME_BYTES: usize = 4 * 1024;
 const MAX_MAX_CLIENT_FRAME_BYTES: usize = 16 * 1024 * 1024;
 
+const TOP_LEVEL_CONFIG_KEYS: &[&str] = &[
+    "general",
+    "network",
+    "server",
+    "timeouts",
+    "censorship",
+    "access",
+    "upstreams",
+    "show_link",
+    "dc_overrides",
+    "default_dc",
+    "beobachten",
+    "beobachten_minutes",
+    "beobachten_flush_secs",
+    "beobachten_file",
+    "include",
+];
+
+const GENERAL_CONFIG_KEYS: &[&str] = &[
+    "data_path",
+    "quota_state_path",
+    "config_strict",
+    "modes",
+    "prefer_ipv6",
+    "fast_mode",
+    "use_middle_proxy",
+    "proxy_secret_path",
+    "proxy_secret_url",
+    "proxy_config_v4_cache_path",
+    "proxy_config_v4_url",
+    "proxy_config_v6_cache_path",
+    "proxy_config_v6_url",
+    "ad_tag",
+    "middle_proxy_nat_ip",
+    "middle_proxy_nat_probe",
+    "middle_proxy_nat_stun",
+    "middle_proxy_nat_stun_servers",
+    "stun_nat_probe_concurrency",
+    "middle_proxy_pool_size",
+    "middle_proxy_warm_standby",
+    "me_init_retry_attempts",
+    "me2dc_fallback",
+    "me2dc_fast",
+    "me_keepalive_enabled",
+    "me_keepalive_interval_secs",
+    "me_keepalive_jitter_secs",
+    "me_keepalive_payload_random",
+    "rpc_proxy_req_every",
+    "me_writer_cmd_channel_capacity",
+    "me_route_channel_capacity",
+    "me_c2me_channel_capacity",
+    "me_c2me_send_timeout_ms",
+    "me_reader_route_data_wait_ms",
+    "me_d2c_flush_batch_max_frames",
+    "me_d2c_flush_batch_max_bytes",
+    "me_d2c_flush_batch_max_delay_us",
+    "me_d2c_ack_flush_immediate",
+    "me_quota_soft_overshoot_bytes",
+    "me_d2c_frame_buf_shrink_threshold_bytes",
+    "direct_relay_copy_buf_c2s_bytes",
+    "direct_relay_copy_buf_s2c_bytes",
+    "crypto_pending_buffer",
+    "max_client_frame",
+    "desync_all_full",
+    "beobachten",
+    "beobachten_minutes",
+    "beobachten_flush_secs",
+    "beobachten_file",
+    "hardswap",
+    "me_warmup_stagger_enabled",
+    "me_warmup_step_delay_ms",
+    "me_warmup_step_jitter_ms",
+    "me_reconnect_max_concurrent_per_dc",
+    "me_reconnect_backoff_base_ms",
+    "me_reconnect_backoff_cap_ms",
+    "me_reconnect_fast_retry_count",
+    "me_single_endpoint_shadow_writers",
+    "me_single_endpoint_outage_mode_enabled",
+    "me_single_endpoint_outage_disable_quarantine",
+    "me_single_endpoint_outage_backoff_min_ms",
+    "me_single_endpoint_outage_backoff_max_ms",
+    "me_single_endpoint_shadow_rotate_every_secs",
+    "me_floor_mode",
+    "me_adaptive_floor_idle_secs",
+    "me_adaptive_floor_min_writers_single_endpoint",
+    "me_adaptive_floor_min_writers_multi_endpoint",
+    "me_adaptive_floor_recover_grace_secs",
+    "me_adaptive_floor_writers_per_core_total",
+    "me_adaptive_floor_cpu_cores_override",
+    "me_adaptive_floor_max_extra_writers_single_per_core",
+    "me_adaptive_floor_max_extra_writers_multi_per_core",
+    "me_adaptive_floor_max_active_writers_per_core",
+    "me_adaptive_floor_max_warm_writers_per_core",
+    "me_adaptive_floor_max_active_writers_global",
+    "me_adaptive_floor_max_warm_writers_global",
+    "upstream_connect_retry_attempts",
+    "upstream_connect_retry_backoff_ms",
+    "upstream_connect_budget_ms",
+    "tg_connect",
+    "upstream_unhealthy_fail_threshold",
+    "upstream_connect_failfast_hard_errors",
+    "stun_iface_mismatch_ignore",
+    "unknown_dc_log_path",
+    "unknown_dc_file_log_enabled",
+    "log_level",
+    "disable_colors",
+    "telemetry",
+    "me_socks_kdf_policy",
+    "me_route_backpressure_enabled",
+    "me_route_fairshare_enabled",
+    "me_route_backpressure_base_timeout_ms",
+    "me_route_backpressure_high_timeout_ms",
+    "me_route_backpressure_high_watermark_pct",
+    "me_health_interval_ms_unhealthy",
+    "me_health_interval_ms_healthy",
+    "me_admission_poll_ms",
+    "me_warn_rate_limit_ms",
+    "me_route_no_writer_mode",
+    "me_route_no_writer_wait_ms",
+    "me_route_hybrid_max_wait_ms",
+    "me_route_blocking_send_timeout_ms",
+    "me_route_inline_recovery_attempts",
+    "me_route_inline_recovery_wait_ms",
+    "links",
+    "fast_mode_min_tls_record",
+    "update_every",
+    "me_reinit_every_secs",
+    "me_hardswap_warmup_delay_min_ms",
+    "me_hardswap_warmup_delay_max_ms",
+    "me_hardswap_warmup_extra_passes",
+    "me_hardswap_warmup_pass_backoff_base_ms",
+    "me_config_stable_snapshots",
+    "me_config_apply_cooldown_secs",
+    "me_snapshot_require_http_2xx",
+    "me_snapshot_reject_empty_map",
+    "me_snapshot_min_proxy_for_lines",
+    "proxy_secret_stable_snapshots",
+    "proxy_secret_rotate_runtime",
+    "me_secret_atomic_snapshot",
+    "proxy_secret_len_max",
+    "me_pool_drain_ttl_secs",
+    "me_instadrain",
+    "me_pool_drain_threshold",
+    "me_pool_drain_soft_evict_enabled",
+    "me_pool_drain_soft_evict_grace_secs",
+    "me_pool_drain_soft_evict_per_writer",
+    "me_pool_drain_soft_evict_budget_per_core",
+    "me_pool_drain_soft_evict_cooldown_ms",
+    "me_bind_stale_mode",
+    "me_bind_stale_ttl_secs",
+    "me_pool_min_fresh_ratio",
+    "me_reinit_drain_timeout_secs",
+    "proxy_secret_auto_reload_secs",
+    "proxy_config_auto_reload_secs",
+    "me_reinit_singleflight",
+    "me_reinit_trigger_channel",
+    "me_reinit_coalesce_window_ms",
+    "me_deterministic_writer_sort",
+    "me_writer_pick_mode",
+    "me_writer_pick_sample_size",
+    "ntp_check",
+    "ntp_servers",
+    "auto_degradation_enabled",
+    "degradation_min_unavailable_dc_groups",
+    "rst_on_close",
+];
+
+const NETWORK_CONFIG_KEYS: &[&str] = &[
+    "ipv4",
+    "ipv6",
+    "prefer",
+    "multipath",
+    "stun_use",
+    "stun_servers",
+    "stun_tcp_fallback",
+    "http_ip_detect_urls",
+    "cache_public_ip_path",
+    "dns_overrides",
+];
+
+const SERVER_CONFIG_KEYS: &[&str] = &[
+    "port",
+    "listen_addr_ipv4",
+    "listen_addr_ipv6",
+    "listen_unix_sock",
+    "listen_unix_sock_perm",
+    "listen_tcp",
+    "proxy_protocol",
+    "proxy_protocol_header_timeout_ms",
+    "proxy_protocol_trusted_cidrs",
+    "metrics_port",
+    "metrics_listen",
+    "metrics_whitelist",
+    "api",
+    "admin_api",
+    "listeners",
+    "listen_backlog",
+    "max_connections",
+    "accept_permit_timeout_ms",
+    "conntrack_control",
+];
+
+const API_CONFIG_KEYS: &[&str] = &[
+    "enabled",
+    "listen",
+    "whitelist",
+    "gray_action",
+    "auth_header",
+    "request_body_limit_bytes",
+    "minimal_runtime_enabled",
+    "minimal_runtime_cache_ttl_ms",
+    "runtime_edge_enabled",
+    "runtime_edge_cache_ttl_ms",
+    "runtime_edge_top_n",
+    "runtime_edge_events_capacity",
+    "read_only",
+];
+
+const CONNTRACK_CONTROL_CONFIG_KEYS: &[&str] = &[
+    "inline_conntrack_control",
+    "mode",
+    "backend",
+    "profile",
+    "hybrid_listener_ips",
+    "pressure_high_watermark_pct",
+    "pressure_low_watermark_pct",
+    "delete_budget_per_sec",
+];
+
+const LISTENER_CONFIG_KEYS: &[&str] = &[
+    "ip",
+    "port",
+    "announce",
+    "announce_ip",
+    "proxy_protocol",
+    "reuse_allow",
+];
+
+const TIMEOUTS_CONFIG_KEYS: &[&str] = &[
+    "client_first_byte_idle_secs",
+    "client_handshake",
+    "relay_idle_policy_v2_enabled",
+    "relay_client_idle_soft_secs",
+    "relay_client_idle_hard_secs",
+    "relay_idle_grace_after_downstream_activity_secs",
+    "client_keepalive",
+    "client_ack",
+    "me_one_retry",
+    "me_one_timeout_ms",
+];
+
+const CENSORSHIP_CONFIG_KEYS: &[&str] = &[
+    "tls_domain",
+    "tls_domains",
+    "unknown_sni_action",
+    "tls_fetch_scope",
+    "tls_fetch",
+    "mask",
+    "mask_host",
+    "mask_port",
+    "mask_unix_sock",
+    "fake_cert_len",
+    "tls_emulation",
+    "tls_front_dir",
+    "server_hello_delay_min_ms",
+    "server_hello_delay_max_ms",
+    "tls_new_session_tickets",
+    "serverhello_compact",
+    "tls_full_cert_ttl_secs",
+    "alpn_enforce",
+    "mask_proxy_protocol",
+    "mask_shape_hardening",
+    "mask_shape_hardening_aggressive_mode",
+    "mask_shape_bucket_floor_bytes",
+    "mask_shape_bucket_cap_bytes",
+    "mask_shape_above_cap_blur",
+    "mask_shape_above_cap_blur_max_bytes",
+    "mask_relay_max_bytes",
+    "mask_relay_timeout_ms",
+    "mask_relay_idle_timeout_ms",
+    "mask_classifier_prefetch_timeout_ms",
+    "mask_timing_normalization_enabled",
+    "mask_timing_normalization_floor_ms",
+    "mask_timing_normalization_ceiling_ms",
+];
+
+const TLS_FETCH_CONFIG_KEYS: &[&str] = &[
+    "profiles",
+    "strict_route",
+    "attempt_timeout_ms",
+    "total_budget_ms",
+    "grease_enabled",
+    "deterministic",
+    "profile_cache_ttl_secs",
+];
+
+const ACCESS_CONFIG_KEYS: &[&str] = &[
+    "users",
+    "user_ad_tags",
+    "user_max_tcp_conns",
+    "user_max_tcp_conns_global_each",
+    "user_expirations",
+    "user_data_quota",
+    "user_rate_limits",
+    "cidr_rate_limits",
+    "user_max_unique_ips",
+    "user_max_unique_ips_global_each",
+    "user_max_unique_ips_mode",
+    "user_max_unique_ips_window_secs",
+    "replay_check_len",
+    "replay_window_secs",
+    "ignore_time_skew",
+];
+
+const RATE_LIMIT_BPS_CONFIG_KEYS: &[&str] = &["up_bps", "down_bps"];
+
+const UPSTREAM_CONFIG_KEYS: &[&str] = &[
+    "type",
+    "interface",
+    "bind_addresses",
+    "bindtodevice",
+    "force_bind",
+    "address",
+    "user_id",
+    "username",
+    "password",
+    "url",
+    "weight",
+    "enabled",
+    "scopes",
+    "ipv4",
+    "ipv6",
+];
+
+const PROXY_MODES_CONFIG_KEYS: &[&str] = &["classic", "secure", "tls"];
+const TELEMETRY_CONFIG_KEYS: &[&str] = &["core_enabled", "user_enabled", "me_level"];
+const LINKS_CONFIG_KEYS: &[&str] = &["show", "public_host", "public_port"];
+
+#[derive(Debug)]
+struct UnknownConfigKey {
+    path: String,
+    suggestion: Option<String>,
+}
+
+fn table_at<'a>(value: &'a toml::Value, path: &[&str]) -> Option<&'a toml::Table> {
+    let mut current = value;
+    for segment in path {
+        current = current.get(*segment)?;
+    }
+    current.as_table()
+}
+
+fn is_strict_config(parsed_toml: &toml::Value) -> bool {
+    table_at(parsed_toml, &["general"])
+        .and_then(|table| table.get("config_strict"))
+        .and_then(toml::Value::as_bool)
+        .unwrap_or(false)
+}
+
+fn known_config_keys_for_suggestion() -> Vec<&'static str> {
+    let mut keys = Vec::new();
+    for group in [
+        TOP_LEVEL_CONFIG_KEYS,
+        GENERAL_CONFIG_KEYS,
+        NETWORK_CONFIG_KEYS,
+        SERVER_CONFIG_KEYS,
+        API_CONFIG_KEYS,
+        CONNTRACK_CONTROL_CONFIG_KEYS,
+        LISTENER_CONFIG_KEYS,
+        TIMEOUTS_CONFIG_KEYS,
+        CENSORSHIP_CONFIG_KEYS,
+        TLS_FETCH_CONFIG_KEYS,
+        ACCESS_CONFIG_KEYS,
+        RATE_LIMIT_BPS_CONFIG_KEYS,
+        UPSTREAM_CONFIG_KEYS,
+        PROXY_MODES_CONFIG_KEYS,
+        TELEMETRY_CONFIG_KEYS,
+        LINKS_CONFIG_KEYS,
+    ] {
+        keys.extend_from_slice(group);
+    }
+    keys
+}
+
+fn levenshtein_distance(a: &str, b: &str) -> usize {
+    let b_chars: Vec<char> = b.chars().collect();
+    let mut prev: Vec<usize> = (0..=b_chars.len()).collect();
+    let mut curr = vec![0usize; b_chars.len() + 1];
+
+    for (i, ca) in a.chars().enumerate() {
+        curr[0] = i + 1;
+        for (j, cb) in b_chars.iter().enumerate() {
+            let replace = if ca == *cb { prev[j] } else { prev[j] + 1 };
+            curr[j + 1] = (prev[j + 1] + 1).min(curr[j] + 1).min(replace);
+        }
+        std::mem::swap(&mut prev, &mut curr);
+    }
+
+    prev[b_chars.len()]
+}
+
+fn unknown_key_suggestion(key: &str, known_keys: &[&'static str]) -> Option<String> {
+    let normalized = key.to_ascii_lowercase();
+    let mut best: Option<(&str, usize)> = None;
+    for known in known_keys {
+        let distance = levenshtein_distance(&normalized, known);
+        let is_better = match best {
+            Some((_, best_distance)) => distance < best_distance,
+            None => true,
+        };
+        if distance <= 4 && is_better {
+            best = Some((known, distance));
+        }
+    }
+    best.map(|(known, _)| known.to_string())
+}
+
+fn push_unknown_keys(
+    unknown: &mut Vec<UnknownConfigKey>,
+    known_for_suggestion: &[&'static str],
+    path: &str,
+    table: &toml::Table,
+    allowed: &[&str],
+) {
+    for key in table.keys() {
+        if !allowed.contains(&key.as_str()) {
+            let full_path = if path.is_empty() {
+                key.clone()
+            } else {
+                format!("{path}.{key}")
+            };
+            unknown.push(UnknownConfigKey {
+                path: full_path,
+                suggestion: unknown_key_suggestion(key, known_for_suggestion),
+            });
+        }
+    }
+}
+
+fn check_known_table(
+    parsed_toml: &toml::Value,
+    unknown: &mut Vec<UnknownConfigKey>,
+    known_for_suggestion: &[&'static str],
+    path: &[&str],
+    allowed: &[&str],
+) {
+    if let Some(table) = table_at(parsed_toml, path) {
+        push_unknown_keys(
+            unknown,
+            known_for_suggestion,
+            &path.join("."),
+            table,
+            allowed,
+        );
+    }
+}
+
+fn check_nested_table_value(
+    unknown: &mut Vec<UnknownConfigKey>,
+    known_for_suggestion: &[&'static str],
+    path: String,
+    value: &toml::Value,
+    allowed: &[&str],
+) {
+    if let Some(table) = value.as_table() {
+        push_unknown_keys(unknown, known_for_suggestion, &path, table, allowed);
+    }
+}
+
+fn collect_unknown_config_keys(parsed_toml: &toml::Value) -> Vec<UnknownConfigKey> {
+    let known_for_suggestion = known_config_keys_for_suggestion();
+    let mut unknown = Vec::new();
+
+    if let Some(root) = parsed_toml.as_table() {
+        push_unknown_keys(
+            &mut unknown,
+            &known_for_suggestion,
+            "",
+            root,
+            TOP_LEVEL_CONFIG_KEYS,
+        );
+    }
+
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["general"],
+        GENERAL_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["general", "modes"],
+        PROXY_MODES_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["general", "telemetry"],
+        TELEMETRY_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["general", "links"],
+        LINKS_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["network"],
+        NETWORK_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["server"],
+        SERVER_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["server", "api"],
+        API_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["server", "admin_api"],
+        API_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["server", "conntrack_control"],
+        CONNTRACK_CONTROL_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["timeouts"],
+        TIMEOUTS_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["censorship"],
+        CENSORSHIP_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["censorship", "tls_fetch"],
+        TLS_FETCH_CONFIG_KEYS,
+    );
+    check_known_table(
+        parsed_toml,
+        &mut unknown,
+        &known_for_suggestion,
+        &["access"],
+        ACCESS_CONFIG_KEYS,
+    );
+
+    if let Some(listeners) = table_at(parsed_toml, &["server"])
+        .and_then(|table| table.get("listeners"))
+        .and_then(toml::Value::as_array)
+    {
+        for (idx, listener) in listeners.iter().enumerate() {
+            check_nested_table_value(
+                &mut unknown,
+                &known_for_suggestion,
+                format!("server.listeners[{idx}]"),
+                listener,
+                LISTENER_CONFIG_KEYS,
+            );
+        }
+    }
+
+    if let Some(upstreams) = parsed_toml
+        .get("upstreams")
+        .and_then(toml::Value::as_array)
+    {
+        for (idx, upstream) in upstreams.iter().enumerate() {
+            check_nested_table_value(
+                &mut unknown,
+                &known_for_suggestion,
+                format!("upstreams[{idx}]"),
+                upstream,
+                UPSTREAM_CONFIG_KEYS,
+            );
+        }
+    }
+
+    for access_map in ["user_rate_limits", "cidr_rate_limits"] {
+        if let Some(table) = table_at(parsed_toml, &["access"])
+            .and_then(|access| access.get(access_map))
+            .and_then(toml::Value::as_table)
+        {
+            for (entry_name, value) in table {
+                check_nested_table_value(
+                    &mut unknown,
+                    &known_for_suggestion,
+                    format!("access.{access_map}.{entry_name}"),
+                    value,
+                    RATE_LIMIT_BPS_CONFIG_KEYS,
+                );
+            }
+        }
+    }
+
+    unknown
+}
+
+fn handle_unknown_config_keys(parsed_toml: &toml::Value) -> Result<()> {
+    let unknown = collect_unknown_config_keys(parsed_toml);
+    if unknown.is_empty() {
+        return Ok(());
+    }
+
+    for item in &unknown {
+        if let Some(suggestion) = item.suggestion.as_deref() {
+            warn!(
+                key = %item.path,
+                suggestion = %suggestion,
+                "Unknown config key ignored; did you mean the suggested key?"
+            );
+        } else {
+            warn!(key = %item.path, "Unknown config key ignored");
+        }
+    }
+
+    if is_strict_config(parsed_toml) {
+        let mut paths = Vec::with_capacity(unknown.len());
+        for item in unknown {
+            if let Some(suggestion) = item.suggestion {
+                paths.push(format!("{} (did you mean `{}`?)", item.path, suggestion));
+            } else {
+                paths.push(item.path);
+            }
+        }
+        return Err(ProxyError::Config(format!(
+            "unknown config keys are not allowed when general.config_strict=true: {}",
+            paths.join(", ")
+        )));
+    }
+
+    Ok(())
+}
+
 #[derive(Debug, Clone)]
 pub(crate) struct LoadedConfig {
     pub(crate) config: ProxyConfig,
@@ -337,6 +998,7 @@ impl ProxyConfig {
 
         let parsed_toml: toml::Value =
             toml::from_str(&processed).map_err(|e| ProxyError::Config(e.to_string()))?;
+        handle_unknown_config_keys(&parsed_toml)?;
         let general_table = parsed_toml
             .get("general")
             .and_then(|value| value.as_table());
@@ -1087,9 +1749,9 @@ impl ProxyConfig {
             ));
         }
 
-        if config.general.me_route_blocking_send_timeout_ms > 5000 {
+        if !(1..=5000).contains(&config.general.me_route_blocking_send_timeout_ms) {
             return Err(ProxyError::Config(
-                "general.me_route_blocking_send_timeout_ms must be within [0, 5000]".to_string(),
+                "general.me_route_blocking_send_timeout_ms must be within [1, 5000]".to_string(),
             ));
         }
 
@@ -2602,6 +3264,26 @@ mod tests {
         let _ = std::fs::remove_file(path);
     }
 
+    #[test]
+    fn me_route_blocking_send_timeout_ms_zero_is_rejected() {
+        let toml = r#"
+            [general]
+            me_route_blocking_send_timeout_ms = 0
+
+            [censorship]
+            tls_domain = "example.com"
+
+            [access.users]
+            user = "00000000000000000000000000000000"
+        "#;
+        let dir = std::env::temp_dir();
+        let path = dir.join("telemt_me_route_blocking_send_timeout_zero_test.toml");
+        std::fs::write(&path, toml).unwrap();
+        let err = ProxyConfig::load(&path).unwrap_err().to_string();
+        assert!(err.contains("general.me_route_blocking_send_timeout_ms must be within [1, 5000]"));
+        let _ = std::fs::remove_file(path);
+    }
+
     #[test]
     fn me_route_no_writer_mode_is_parsed() {
         let toml = r#"

src/config/types.rs

@@ -26,6 +26,10 @@ pub enum LogLevel {
     Silent,
 }
 
+fn default_quota_state_path() -> PathBuf {
+    PathBuf::from("telemt.limit.json")
+}
+
 impl LogLevel {
     /// Convert to tracing EnvFilter directive string.
     pub fn to_filter_str(&self) -> &'static str {
@@ -375,6 +379,15 @@ pub struct GeneralConfig {
     #[serde(default)]
     pub data_path: Option<PathBuf>,
 
+    /// JSON state file for runtime per-user quota consumption.
+    #[serde(default = "default_quota_state_path")]
+    pub quota_state_path: PathBuf,
+
+    /// Reject unknown TOML config keys during load.
+    /// Startup fails fast; hot-reload rejects the new snapshot and keeps the current config.
+    #[serde(default)]
+    pub config_strict: bool,
+
     #[serde(default)]
     pub modes: ProxyModes,
 
@@ -778,7 +791,7 @@ pub struct GeneralConfig {
     pub me_route_hybrid_max_wait_ms: u64,
 
     /// Maximum wait in milliseconds for blocking ME writer channel send fallback.
-    /// `0` keeps legacy unbounded wait behavior.
+    /// Must be within [1, 5000].
     #[serde(default = "default_me_route_blocking_send_timeout_ms")]
     pub me_route_blocking_send_timeout_ms: u64,
 
@@ -974,6 +987,8 @@ impl Default for GeneralConfig {
     fn default() -> Self {
         Self {
             data_path: None,
+            quota_state_path: default_quota_state_path(),
+            config_strict: false,
             modes: ProxyModes::default(),
             prefer_ipv6: false,
             fast_mode: default_true(),
@@ -1887,6 +1902,12 @@ pub struct AccessConfig {
     #[serde(default)]
     pub cidr_rate_limits: HashMap<IpNetwork, RateLimitBps>,
 
+    /// Per-username client source IP/CIDR deny list. Checked after successful
+    /// authentication; matching IPs get the same rejection path as invalid auth
+    /// (handshake fails closed for that connection).
+    #[serde(default)]
+    pub user_source_deny: HashMap<String, Vec<IpNetwork>>,
+
     #[serde(default)]
     pub user_max_unique_ips: HashMap<String, usize>,
 
@@ -1922,6 +1943,7 @@ impl Default for AccessConfig {
             user_data_quota: HashMap::new(),
             user_rate_limits: HashMap::new(),
             cidr_rate_limits: HashMap::new(),
+            user_source_deny: HashMap::new(),
             user_max_unique_ips: HashMap::new(),
             user_max_unique_ips_global_each: default_user_max_unique_ips_global_each(),
             user_max_unique_ips_mode: UserMaxUniqueIpsMode::default(),
@@ -1933,6 +1955,15 @@ impl Default for AccessConfig {
     }
 }
 
+impl AccessConfig {
+    /// Returns true if `ip` is contained in any CIDR listed for `username` under `user_source_deny`.
+    pub fn is_user_source_ip_denied(&self, username: &str, ip: IpAddr) -> bool {
+        self.user_source_deny
+            .get(username)
+            .is_some_and(|nets| nets.iter().any(|n| n.contains(ip)))
+    }
+}
+
 #[derive(Debug, Clone, Copy, Default, PartialEq, Eq, Serialize, Deserialize)]
 pub struct RateLimitBps {
     #[serde(default)]

src/ip_tracker.rs

@@ -9,14 +9,24 @@ use std::sync::Mutex;
 use std::sync::atomic::{AtomicU64, Ordering};
 use std::time::{Duration, Instant};
 
-use tokio::sync::{Mutex as AsyncMutex, RwLock};
+use tokio::sync::{Mutex as AsyncMutex, RwLock, RwLockWriteGuard};
 
 use crate::config::UserMaxUniqueIpsMode;
 
+const CLEANUP_DRAIN_BATCH_LIMIT: usize = 1024;
+const MAX_ACTIVE_IP_ENTRIES: u64 = 131_072;
+const MAX_RECENT_IP_ENTRIES: u64 = 262_144;
+
+/// Tracks active and recent client IPs for per-user admission control.
 #[derive(Debug, Clone)]
 pub struct UserIpTracker {
     active_ips: Arc<RwLock<HashMap<String, HashMap<IpAddr, usize>>>>,
     recent_ips: Arc<RwLock<HashMap<String, HashMap<IpAddr, Instant>>>>,
+    active_entry_count: Arc<AtomicU64>,
+    recent_entry_count: Arc<AtomicU64>,
+    active_cap_rejects: Arc<AtomicU64>,
+    recent_cap_rejects: Arc<AtomicU64>,
+    cleanup_deferred_releases: Arc<AtomicU64>,
     max_ips: Arc<RwLock<HashMap<String, usize>>>,
     default_max_ips: Arc<RwLock<usize>>,
     limit_mode: Arc<RwLock<UserMaxUniqueIpsMode>>,
@@ -26,13 +36,25 @@ pub struct UserIpTracker {
     cleanup_drain_lock: Arc<AsyncMutex<()>>,
 }
 
+/// Point-in-time memory counters for user/IP limiter state.
 #[derive(Debug, Clone, Copy)]
 pub struct UserIpTrackerMemoryStats {
+    /// Number of users with active IP state.
     pub active_users: usize,
+    /// Number of users with recent IP state.
     pub recent_users: usize,
+    /// Number of active `(user, ip)` entries.
     pub active_entries: usize,
+    /// Number of recent-window `(user, ip)` entries.
     pub recent_entries: usize,
+    /// Number of deferred disconnect cleanups waiting to be drained.
     pub cleanup_queue_len: usize,
+    /// Number of new connections rejected by the global active-entry cap.
+    pub active_cap_rejects: u64,
+    /// Number of new connections rejected by the global recent-entry cap.
+    pub recent_cap_rejects: u64,
+    /// Number of release cleanups deferred through the cleanup queue.
+    pub cleanup_deferred_releases: u64,
 }
 
 impl UserIpTracker {
@@ -40,6 +62,11 @@ impl UserIpTracker {
         Self {
             active_ips: Arc::new(RwLock::new(HashMap::new())),
             recent_ips: Arc::new(RwLock::new(HashMap::new())),
+            active_entry_count: Arc::new(AtomicU64::new(0)),
+            recent_entry_count: Arc::new(AtomicU64::new(0)),
+            active_cap_rejects: Arc::new(AtomicU64::new(0)),
+            recent_cap_rejects: Arc::new(AtomicU64::new(0)),
+            cleanup_deferred_releases: Arc::new(AtomicU64::new(0)),
             max_ips: Arc::new(RwLock::new(HashMap::new())),
             default_max_ips: Arc::new(RwLock::new(0)),
             limit_mode: Arc::new(RwLock::new(UserMaxUniqueIpsMode::ActiveWindow)),
@@ -50,16 +77,59 @@ impl UserIpTracker {
         }
     }
 
+    fn decrement_counter(counter: &AtomicU64, amount: usize) {
+        if amount == 0 {
+            return;
+        }
+        let amount = amount as u64;
+        let _ = counter.fetch_update(Ordering::AcqRel, Ordering::Relaxed, |current| {
+            Some(current.saturating_sub(amount))
+        });
+    }
+
+    fn apply_active_cleanup(
+        active_ips: &mut HashMap<String, HashMap<IpAddr, usize>>,
+        user: &str,
+        ip: IpAddr,
+        pending_count: usize,
+    ) -> usize {
+        if pending_count == 0 {
+            return 0;
+        }
+
+        let mut remove_user = false;
+        let mut removed_active_entries = 0usize;
+        if let Some(user_ips) = active_ips.get_mut(user) {
+            if let Some(count) = user_ips.get_mut(&ip) {
+                if *count > pending_count {
+                    *count -= pending_count;
+                } else if user_ips.remove(&ip).is_some() {
+                    removed_active_entries = 1;
+                }
+            }
+            remove_user = user_ips.is_empty();
+        }
+        if remove_user {
+            active_ips.remove(user);
+        }
+        removed_active_entries
+    }
+
+    /// Queues a deferred active IP cleanup for a later async drain.
     pub fn enqueue_cleanup(&self, user: String, ip: IpAddr) {
         match self.cleanup_queue.lock() {
             Ok(mut queue) => {
                 let count = queue.entry((user, ip)).or_insert(0);
                 *count = count.saturating_add(1);
+                self.cleanup_deferred_releases
+                    .fetch_add(1, Ordering::Relaxed);
             }
             Err(poisoned) => {
                 let mut queue = poisoned.into_inner();
                 let count = queue.entry((user.clone(), ip)).or_insert(0);
                 *count = count.saturating_add(1);
+                self.cleanup_deferred_releases
+                    .fetch_add(1, Ordering::Relaxed);
                 self.cleanup_queue.clear_poison();
                 tracing::warn!(
                     "UserIpTracker cleanup_queue lock poisoned; recovered and enqueued IP cleanup for {} ({})",
@@ -86,16 +156,27 @@ impl UserIpTracker {
     }
 
     pub(crate) async fn drain_cleanup_queue(&self) {
-        // Serialize queue draining and active-IP mutation so check-and-add cannot
-        // observe stale active entries that are already queued for removal.
-        let _drain_guard = self.cleanup_drain_lock.lock().await;
+        let Ok(_drain_guard) = self.cleanup_drain_lock.try_lock() else {
+            return;
+        };
+
         let to_remove = {
             match self.cleanup_queue.lock() {
                 Ok(mut queue) => {
                     if queue.is_empty() {
                         return;
                     }
-                    std::mem::take(&mut *queue)
+                    let mut drained =
+                        HashMap::with_capacity(queue.len().min(CLEANUP_DRAIN_BATCH_LIMIT));
+                    for _ in 0..CLEANUP_DRAIN_BATCH_LIMIT {
+                        let Some(key) = queue.keys().next().cloned() else {
+                            break;
+                        };
+                        if let Some(count) = queue.remove(&key) {
+                            drained.insert(key, count);
+                        }
+                    }
+                    drained
                 }
                 Err(poisoned) => {
                     let mut queue = poisoned.into_inner();
@@ -103,31 +184,33 @@ impl UserIpTracker {
                         self.cleanup_queue.clear_poison();
                         return;
                     }
-                    let drained = std::mem::take(&mut *queue);
+                    let mut drained =
+                        HashMap::with_capacity(queue.len().min(CLEANUP_DRAIN_BATCH_LIMIT));
+                    for _ in 0..CLEANUP_DRAIN_BATCH_LIMIT {
+                        let Some(key) = queue.keys().next().cloned() else {
+                            break;
+                        };
+                        if let Some(count) = queue.remove(&key) {
+                            drained.insert(key, count);
+                        }
+                    }
                     self.cleanup_queue.clear_poison();
                     drained
                 }
             }
         };
+        if to_remove.is_empty() {
+            return;
+        }
 
         let mut active_ips = self.active_ips.write().await;
+        let mut removed_active_entries = 0usize;
         for ((user, ip), pending_count) in to_remove {
-            if pending_count == 0 {
-                continue;
-            }
-            if let Some(user_ips) = active_ips.get_mut(&user) {
-                if let Some(count) = user_ips.get_mut(&ip) {
-                    if *count > pending_count {
-                        *count -= pending_count;
-                    } else {
-                        user_ips.remove(&ip);
-                    }
-                }
-                if user_ips.is_empty() {
-                    active_ips.remove(&user);
-                }
-            }
+            removed_active_entries = removed_active_entries.saturating_add(
+                Self::apply_active_cleanup(&mut active_ips, &user, ip, pending_count),
+            );
         }
+        Self::decrement_counter(&self.active_entry_count, removed_active_entries);
     }
 
     fn now_epoch_secs() -> u64 {
@@ -137,6 +220,24 @@ impl UserIpTracker {
             .as_secs()
     }
 
+    async fn active_and_recent_write(
+        &self,
+    ) -> (
+        RwLockWriteGuard<'_, HashMap<String, HashMap<IpAddr, usize>>>,
+        RwLockWriteGuard<'_, HashMap<String, HashMap<IpAddr, Instant>>>,
+    ) {
+        loop {
+            let active_ips = self.active_ips.write().await;
+            match self.recent_ips.try_write() {
+                Ok(recent_ips) => return (active_ips, recent_ips),
+                Err(_) => {
+                    drop(active_ips);
+                    tokio::task::yield_now().await;
+                }
+            }
+        }
+    }
+
     async fn maybe_compact_empty_users(&self) {
         const COMPACT_INTERVAL_SECS: u64 = 60;
         let now_epoch_secs = Self::now_epoch_secs();
@@ -157,14 +258,16 @@ impl UserIpTracker {
             return;
         }
 
-        let mut active_ips = self.active_ips.write().await;
-        let mut recent_ips = self.recent_ips.write().await;
         let window = *self.limit_window.read().await;
         let now = Instant::now();
+        let (mut active_ips, mut recent_ips) = self.active_and_recent_write().await;
 
+        let mut pruned_recent_entries = 0usize;
         for user_recent in recent_ips.values_mut() {
-            Self::prune_recent(user_recent, now, window);
+            pruned_recent_entries =
+                pruned_recent_entries.saturating_add(Self::prune_recent(user_recent, now, window));
         }
+        Self::decrement_counter(&self.recent_entry_count, pruned_recent_entries);
 
         let mut users =
             Vec::<String>::with_capacity(active_ips.len().saturating_add(recent_ips.len()));
@@ -208,6 +311,9 @@ impl UserIpTracker {
             active_entries,
             recent_entries,
             cleanup_queue_len,
+            active_cap_rejects: self.active_cap_rejects.load(Ordering::Relaxed),
+            recent_cap_rejects: self.recent_cap_rejects.load(Ordering::Relaxed),
+            cleanup_deferred_releases: self.cleanup_deferred_releases.load(Ordering::Relaxed),
         }
     }
 
@@ -238,11 +344,17 @@ impl UserIpTracker {
         max_ips.clone_from(limits);
     }
 
-    fn prune_recent(user_recent: &mut HashMap<IpAddr, Instant>, now: Instant, window: Duration) {
+    fn prune_recent(
+        user_recent: &mut HashMap<IpAddr, Instant>,
+        now: Instant,
+        window: Duration,
+    ) -> usize {
         if user_recent.is_empty() {
-            return;
+            return 0;
         }
+        let before = user_recent.len();
         user_recent.retain(|_, seen_at| now.duration_since(*seen_at) <= window);
+        before.saturating_sub(user_recent.len())
     }
 
     pub async fn check_and_add(&self, username: &str, ip: IpAddr) -> Result<(), String> {
@@ -261,26 +373,40 @@ impl UserIpTracker {
         let window = *self.limit_window.read().await;
         let now = Instant::now();
 
-        let mut active_ips = self.active_ips.write().await;
+        let (mut active_ips, mut recent_ips) = self.active_and_recent_write().await;
         let user_active = active_ips
             .entry(username.to_string())
             .or_insert_with(HashMap::new);
-
-        let mut recent_ips = self.recent_ips.write().await;
         let user_recent = recent_ips
             .entry(username.to_string())
             .or_insert_with(HashMap::new);
-        Self::prune_recent(user_recent, now, window);
+        let pruned_recent_entries = Self::prune_recent(user_recent, now, window);
+        Self::decrement_counter(&self.recent_entry_count, pruned_recent_entries);
+        let recent_contains_ip = user_recent.contains_key(&ip);
 
         if let Some(count) = user_active.get_mut(&ip) {
+            if !recent_contains_ip
+                && self.recent_entry_count.load(Ordering::Relaxed) >= MAX_RECENT_IP_ENTRIES
+            {
+                self.recent_cap_rejects.fetch_add(1, Ordering::Relaxed);
+                return Err(format!(
+                    "IP tracker recent entry cap reached: entries={}/{}",
+                    self.recent_entry_count.load(Ordering::Relaxed),
+                    MAX_RECENT_IP_ENTRIES
+                ));
+            }
             *count = count.saturating_add(1);
-            user_recent.insert(ip, now);
+            if user_recent.insert(ip, now).is_none() {
+                self.recent_entry_count.fetch_add(1, Ordering::Relaxed);
+            }
             return Ok(());
         }
 
+        let is_new_ip = !recent_contains_ip;
+
         if let Some(limit) = limit {
             let active_limit_reached = user_active.len() >= limit;
-            let recent_limit_reached = user_recent.len() >= limit;
+            let recent_limit_reached = user_recent.len() >= limit && is_new_ip;
             let deny = match mode {
                 UserMaxUniqueIpsMode::ActiveWindow => active_limit_reached,
                 UserMaxUniqueIpsMode::TimeWindow => recent_limit_reached,
@@ -300,30 +426,62 @@ impl UserIpTracker {
             }
         }
 
-        user_active.insert(ip, 1);
-        user_recent.insert(ip, now);
+        if self.active_entry_count.load(Ordering::Relaxed) >= MAX_ACTIVE_IP_ENTRIES {
+            self.active_cap_rejects.fetch_add(1, Ordering::Relaxed);
+            return Err(format!(
+                "IP tracker active entry cap reached: entries={}/{}",
+                self.active_entry_count.load(Ordering::Relaxed),
+                MAX_ACTIVE_IP_ENTRIES
+            ));
+        }
+        if is_new_ip && self.recent_entry_count.load(Ordering::Relaxed) >= MAX_RECENT_IP_ENTRIES {
+            self.recent_cap_rejects.fetch_add(1, Ordering::Relaxed);
+            return Err(format!(
+                "IP tracker recent entry cap reached: entries={}/{}",
+                self.recent_entry_count.load(Ordering::Relaxed),
+                MAX_RECENT_IP_ENTRIES
+            ));
+        }
+
+        if user_active.insert(ip, 1).is_none() {
+            self.active_entry_count.fetch_add(1, Ordering::Relaxed);
+        }
+        if user_recent.insert(ip, now).is_none() {
+            self.recent_entry_count.fetch_add(1, Ordering::Relaxed);
+        }
         Ok(())
     }
 
     pub async fn remove_ip(&self, username: &str, ip: IpAddr) {
         self.maybe_compact_empty_users().await;
         let mut active_ips = self.active_ips.write().await;
+        let mut removed_active_entries = 0usize;
         if let Some(user_ips) = active_ips.get_mut(username) {
             if let Some(count) = user_ips.get_mut(&ip) {
                 if *count > 1 {
                     *count -= 1;
                 } else {
-                    user_ips.remove(&ip);
+                    if user_ips.remove(&ip).is_some() {
+                        removed_active_entries = 1;
+                    }
                 }
             }
             if user_ips.is_empty() {
                 active_ips.remove(username);
             }
         }
+        Self::decrement_counter(&self.active_entry_count, removed_active_entries);
     }
 
     pub async fn get_recent_counts_for_users(&self, users: &[String]) -> HashMap<String, usize> {
         self.drain_cleanup_queue().await;
+        self.get_recent_counts_for_users_snapshot(users).await
+    }
+
+    pub(crate) async fn get_recent_counts_for_users_snapshot(
+        &self,
+        users: &[String],
+    ) -> HashMap<String, usize> {
         let window = *self.limit_window.read().await;
         let now = Instant::now();
         let recent_ips = self.recent_ips.read().await;
@@ -398,19 +556,29 @@ impl UserIpTracker {
 
     pub async fn get_stats(&self) -> Vec<(String, usize, usize)> {
         self.drain_cleanup_queue().await;
+        self.get_stats_snapshot().await
+    }
+
+    pub(crate) async fn get_stats_snapshot(&self) -> Vec<(String, usize, usize)> {
         let active_ips = self.active_ips.read().await;
+        let active_counts = active_ips
+            .iter()
+            .map(|(username, user_ips)| (username.clone(), user_ips.len()))
+            .collect::<Vec<_>>();
+        drop(active_ips);
+
         let max_ips = self.max_ips.read().await;
         let default_max_ips = *self.default_max_ips.read().await;
 
-        let mut stats = Vec::new();
-        for (username, user_ips) in active_ips.iter() {
+        let mut stats = Vec::with_capacity(active_counts.len());
+        for (username, active_count) in active_counts {
             let limit = max_ips
-                .get(username)
+                .get(&username)
                 .copied()
                 .filter(|limit| *limit > 0)
                 .or((default_max_ips > 0).then_some(default_max_ips))
                 .unwrap_or(0);
-            stats.push((username.clone(), user_ips.len(), limit));
+            stats.push((username, active_count, limit));
         }
 
         stats.sort_by(|a, b| a.0.cmp(&b.0));
@@ -419,20 +587,30 @@ impl UserIpTracker {
 
     pub async fn clear_user_ips(&self, username: &str) {
         let mut active_ips = self.active_ips.write().await;
-        active_ips.remove(username);
+        let removed_active_entries = active_ips
+            .remove(username)
+            .map(|ips| ips.len())
+            .unwrap_or(0);
         drop(active_ips);
+        Self::decrement_counter(&self.active_entry_count, removed_active_entries);
 
         let mut recent_ips = self.recent_ips.write().await;
-        recent_ips.remove(username);
+        let removed_recent_entries = recent_ips
+            .remove(username)
+            .map(|ips| ips.len())
+            .unwrap_or(0);
+        Self::decrement_counter(&self.recent_entry_count, removed_recent_entries);
     }
 
     pub async fn clear_all(&self) {
         let mut active_ips = self.active_ips.write().await;
         active_ips.clear();
         drop(active_ips);
+        self.active_entry_count.store(0, Ordering::Relaxed);
 
         let mut recent_ips = self.recent_ips.write().await;
         recent_ips.clear();
+        self.recent_entry_count.store(0, Ordering::Relaxed);
     }
 
     pub async fn is_ip_active(&self, username: &str, ip: IpAddr) -> bool {
@@ -860,4 +1038,19 @@ mod tests {
             .unwrap_or(false);
         assert!(!stale_exists);
     }
+
+    #[tokio::test]
+    async fn test_time_window_allows_same_ip_reconnect() {
+        let tracker = UserIpTracker::new();
+        tracker.set_user_limit("test_user", 1).await;
+        tracker
+            .set_limit_policy(UserMaxUniqueIpsMode::TimeWindow, 1)
+            .await;
+
+        let ip1 = test_ipv4(10, 4, 0, 1);
+
+        assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
+        tracker.remove_ip("test_user", ip1).await;
+        assert!(tracker.check_and_add("test_user", ip1).await.is_ok());
+    }
 }

src/maestro/admission.rs

@@ -17,6 +17,7 @@ pub(crate) async fn configure_admission_gate(
     route_runtime: Arc<RouteRuntimeController>,
     admission_tx: &watch::Sender<bool>,
     config_rx: watch::Receiver<Arc<ProxyConfig>>,
+    me_ready_rx: watch::Receiver<u64>,
 ) {
     if config.general.use_middle_proxy {
         if let Some(pool) = me_pool.as_ref() {
@@ -52,6 +53,7 @@ pub(crate) async fn configure_admission_gate(
             let admission_tx_gate = admission_tx.clone();
             let route_runtime_gate = route_runtime.clone();
             let mut config_rx_gate = config_rx.clone();
+            let mut me_ready_rx_gate = me_ready_rx;
             let mut admission_poll_ms = config.general.me_admission_poll_ms.max(1);
             tokio::spawn(async move {
                 let mut gate_open = initial_gate_open;
@@ -74,6 +76,11 @@ pub(crate) async fn configure_admission_gate(
                             fast_fallback_enabled = cfg.general.me2dc_fallback && cfg.general.me2dc_fast;
                             continue;
                         }
+                        changed = me_ready_rx_gate.changed() => {
+                            if changed.is_err() {
+                                break;
+                            }
+                        }
                         _ = tokio::time::sleep(Duration::from_millis(admission_poll_ms)) => {}
                     }
                     let ready = pool_for_gate.admission_ready_conditional_cast().await;

src/maestro/helpers.rs

@@ -1,6 +1,6 @@
 #![allow(clippy::items_after_test_module)]
 
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use std::time::Duration;
 
 use tokio::sync::watch;
@@ -17,7 +17,7 @@ use crate::transport::middle_proxy::{
 
 pub(crate) fn resolve_runtime_config_path(
     config_path_cli: &str,
-    startup_cwd: &std::path::Path,
+    startup_cwd: &Path,
     config_path_explicit: bool,
 ) -> PathBuf {
     if config_path_explicit {
@@ -46,6 +46,39 @@ pub(crate) fn resolve_runtime_config_path(
     startup_cwd.join("config.toml")
 }
 
+pub(crate) fn resolve_runtime_base_dir(
+    config_path: &Path,
+    startup_cwd: &Path,
+    config_path_explicit: bool,
+    data_path: Option<&Path>,
+) -> PathBuf {
+    if let Some(path) = data_path {
+        return normalize_runtime_dir(path, startup_cwd);
+    }
+
+    if startup_cwd != Path::new("/") {
+        return normalize_runtime_dir(startup_cwd, startup_cwd);
+    }
+
+    if config_path_explicit
+        && let Some(parent) = config_path.parent()
+        && !parent.as_os_str().is_empty()
+    {
+        return normalize_runtime_dir(parent, startup_cwd);
+    }
+
+    PathBuf::from("/etc/telemt")
+}
+
+fn normalize_runtime_dir(path: &Path, startup_cwd: &Path) -> PathBuf {
+    let absolute = if path.is_absolute() {
+        path.to_path_buf()
+    } else {
+        startup_cwd.join(path)
+    };
+    absolute.canonicalize().unwrap_or(absolute)
+}
+
 /// Parsed CLI arguments.
 pub(crate) struct CliArgs {
     pub config_path: String,
@@ -231,9 +264,11 @@ fn print_help() {
 
 #[cfg(test)]
 mod tests {
+    use std::path::{Path, PathBuf};
+
     use super::{
         expected_handshake_close_description, is_expected_handshake_eof, peer_close_description,
-        resolve_runtime_config_path,
+        resolve_runtime_base_dir, resolve_runtime_config_path,
     };
     use crate::error::{ProxyError, StreamError};
 
@@ -304,6 +339,91 @@ mod tests {
         let _ = std::fs::remove_dir(&startup_cwd);
     }
 
+    #[test]
+    fn resolve_runtime_base_dir_prefers_cli_data_path() {
+        let nonce = std::time::SystemTime::now()
+            .duration_since(std::time::UNIX_EPOCH)
+            .unwrap()
+            .as_nanos();
+        let startup_cwd = std::env::temp_dir().join(format!("telemt_runtime_base_cwd_{nonce}"));
+        let data_path = std::env::temp_dir().join(format!("telemt_runtime_base_data_{nonce}"));
+        std::fs::create_dir_all(&startup_cwd).unwrap();
+        std::fs::create_dir_all(&data_path).unwrap();
+
+        let resolved = resolve_runtime_base_dir(
+            &startup_cwd.join("config.toml"),
+            &startup_cwd,
+            true,
+            Some(&data_path),
+        );
+        assert_eq!(resolved, data_path.canonicalize().unwrap());
+
+        let _ = std::fs::remove_dir(&data_path);
+        let _ = std::fs::remove_dir(&startup_cwd);
+    }
+
+    #[test]
+    fn resolve_runtime_base_dir_uses_working_directory_before_explicit_config_parent() {
+        let nonce = std::time::SystemTime::now()
+            .duration_since(std::time::UNIX_EPOCH)
+            .unwrap()
+            .as_nanos();
+        let startup_cwd = std::env::temp_dir().join(format!("telemt_runtime_base_start_{nonce}"));
+        let config_dir = std::env::temp_dir().join(format!("telemt_runtime_base_cfg_{nonce}"));
+        std::fs::create_dir_all(&startup_cwd).unwrap();
+        std::fs::create_dir_all(&config_dir).unwrap();
+
+        let resolved =
+            resolve_runtime_base_dir(&config_dir.join("telemt.toml"), &startup_cwd, true, None);
+        assert_eq!(resolved, startup_cwd.canonicalize().unwrap());
+
+        let _ = std::fs::remove_dir(&config_dir);
+        let _ = std::fs::remove_dir(&startup_cwd);
+    }
+
+    #[test]
+    fn resolve_runtime_base_dir_uses_explicit_config_parent_from_root() {
+        let nonce = std::time::SystemTime::now()
+            .duration_since(std::time::UNIX_EPOCH)
+            .unwrap()
+            .as_nanos();
+        let config_dir = std::env::temp_dir().join(format!("telemt_runtime_base_root_cfg_{nonce}"));
+        std::fs::create_dir_all(&config_dir).unwrap();
+
+        let resolved =
+            resolve_runtime_base_dir(&config_dir.join("telemt.toml"), Path::new("/"), true, None);
+        assert_eq!(resolved, config_dir.canonicalize().unwrap());
+
+        let _ = std::fs::remove_dir(&config_dir);
+    }
+
+    #[test]
+    fn resolve_runtime_base_dir_uses_systemd_working_directory_before_etc() {
+        let nonce = std::time::SystemTime::now()
+            .duration_since(std::time::UNIX_EPOCH)
+            .unwrap()
+            .as_nanos();
+        let startup_cwd = std::env::temp_dir().join(format!("telemt_runtime_base_systemd_{nonce}"));
+        std::fs::create_dir_all(&startup_cwd).unwrap();
+
+        let resolved =
+            resolve_runtime_base_dir(&startup_cwd.join("config.toml"), &startup_cwd, false, None);
+        assert_eq!(resolved, startup_cwd.canonicalize().unwrap());
+
+        let _ = std::fs::remove_dir(&startup_cwd);
+    }
+
+    #[test]
+    fn resolve_runtime_base_dir_falls_back_to_etc_from_root() {
+        let resolved = resolve_runtime_base_dir(
+            Path::new("/etc/telemt/config.toml"),
+            Path::new("/"),
+            false,
+            None,
+        );
+        assert_eq!(resolved, PathBuf::from("/etc/telemt"));
+    }
+
     #[test]
     fn expected_handshake_eof_matches_connection_reset() {
         let err = ProxyError::Io(std::io::Error::from(std::io::ErrorKind::ConnectionReset));

src/maestro/me_startup.rs

@@ -3,7 +3,7 @@
 use std::sync::Arc;
 use std::time::Duration;
 
-use tokio::sync::RwLock;
+use tokio::sync::{RwLock, watch};
 use tracing::{error, info, warn};
 
 use crate::config::ProxyConfig;
@@ -29,6 +29,7 @@ pub(crate) async fn initialize_me_pool(
     rng: Arc<SecureRandom>,
     stats: Arc<Stats>,
     api_me_pool: Arc<RwLock<Option<Arc<MePool>>>>,
+    me_ready_tx: watch::Sender<u64>,
 ) -> Option<Arc<MePool>> {
     if !use_middle_proxy {
         return None;
@@ -314,6 +315,7 @@ pub(crate) async fn initialize_me_pool(
                     let pool_bg = pool.clone();
                     let rng_bg = rng.clone();
                     let startup_tracker_bg = startup_tracker.clone();
+                    let me_ready_tx_bg = me_ready_tx.clone();
                     let retry_limit = if me_init_retry_attempts == 0 {
                         String::from("unlimited")
                     } else {
@@ -347,6 +349,9 @@ pub(crate) async fn initialize_me_pool(
                                         startup_tracker_bg
                                             .set_me_status(StartupMeStatus::Ready, "ready")
                                             .await;
+                                        me_ready_tx_bg.send_modify(|version| {
+                                            *version = version.saturating_add(1);
+                                        });
                                         info!(
                                             attempt = init_attempt,
                                             "Middle-End pool initialized successfully"
@@ -474,6 +479,9 @@ pub(crate) async fn initialize_me_pool(
                                 startup_tracker
                                     .set_me_status(StartupMeStatus::Ready, "ready")
                                     .await;
+                                me_ready_tx.send_modify(|version| {
+                                    *version = version.saturating_add(1);
+                                });
                                 info!(
                                     attempt = init_attempt,
                                     "Middle-End pool initialized successfully"

src/maestro/mod.rs

@@ -47,7 +47,7 @@ use crate::stats::{ReplayChecker, Stats};
 use crate::stream::BufferPool;
 use crate::transport::UpstreamManager;
 use crate::transport::middle_proxy::MePool;
-use helpers::{parse_cli, resolve_runtime_config_path};
+use helpers::{parse_cli, resolve_runtime_base_dir, resolve_runtime_config_path};
 
 #[cfg(unix)]
 use crate::daemon::{DaemonOptions, PidFile, drop_privileges};
@@ -112,8 +112,51 @@ async fn run_telemt_core(
             std::process::exit(1);
         }
     };
+    if let Some(ref data_path) = data_path
+        && !data_path.is_absolute()
+    {
+        eprintln!(
+            "[telemt] data_path must be absolute: {}",
+            data_path.display()
+        );
+        std::process::exit(1);
+    }
     let mut config_path =
         resolve_runtime_config_path(&config_path_cli, &startup_cwd, config_path_explicit);
+    let runtime_base_dir = resolve_runtime_base_dir(
+        &config_path,
+        &startup_cwd,
+        config_path_explicit,
+        data_path.as_deref(),
+    );
+
+    if !runtime_base_dir.exists()
+        && let Err(e) = std::fs::create_dir_all(&runtime_base_dir)
+    {
+        eprintln!(
+            "[telemt] Can't create runtime directory {}: {}",
+            runtime_base_dir.display(),
+            e
+        );
+        std::process::exit(1);
+    }
+
+    if !runtime_base_dir.is_dir() {
+        eprintln!(
+            "[telemt] Runtime path exists but is not a directory: {}",
+            runtime_base_dir.display()
+        );
+        std::process::exit(1);
+    }
+
+    if let Err(e) = std::env::set_current_dir(&runtime_base_dir) {
+        eprintln!(
+            "[telemt] Can't use runtime directory {}: {}",
+            runtime_base_dir.display(),
+            e
+        );
+        std::process::exit(1);
+    }
 
     let mut config = match ProxyConfig::load(&config_path) {
         Ok(c) => c,
@@ -156,16 +199,15 @@ async fn run_telemt_core(
                         );
                     }
                 } else {
-                    let system_dir = std::path::Path::new("/etc/telemt");
-                    let system_config_path = system_dir.join("telemt.toml");
-                    let startup_config_path = startup_cwd.join("config.toml");
+                    let runtime_config_path = runtime_base_dir.join("telemt.toml");
+                    let fallback_config_path = runtime_base_dir.join("config.toml");
                     let mut persisted = false;
 
                     if let Some(serialized) = serialized.as_ref() {
-                        match std::fs::create_dir_all(system_dir) {
-                            Ok(()) => match std::fs::write(&system_config_path, serialized) {
+                        match std::fs::create_dir_all(&runtime_base_dir) {
+                            Ok(()) => match std::fs::write(&runtime_config_path, serialized) {
                                 Ok(()) => {
-                                    config_path = system_config_path;
+                                    config_path = runtime_config_path;
                                     eprintln!(
                                         "[telemt] Created default config at {}",
                                         config_path.display()
@@ -175,7 +217,7 @@ async fn run_telemt_core(
                                 Err(write_error) => {
                                     eprintln!(
                                         "[telemt] Warning: failed to write default config at {}: {}",
-                                        system_config_path.display(),
+                                        runtime_config_path.display(),
                                         write_error
                                     );
                                 }
@@ -183,16 +225,16 @@ async fn run_telemt_core(
                             Err(create_error) => {
                                 eprintln!(
                                     "[telemt] Warning: failed to create {}: {}",
-                                    system_dir.display(),
+                                    runtime_base_dir.display(),
                                     create_error
                                 );
                             }
                         }
 
                         if !persisted {
-                            match std::fs::write(&startup_config_path, serialized) {
+                            match std::fs::write(&fallback_config_path, serialized) {
                                 Ok(()) => {
-                                    config_path = startup_config_path;
+                                    config_path = fallback_config_path;
                                     eprintln!(
                                         "[telemt] Created default config at {}",
                                         config_path.display()
@@ -202,7 +244,7 @@ async fn run_telemt_core(
                                 Err(write_error) => {
                                     eprintln!(
                                         "[telemt] Warning: failed to write default config at {}: {}",
-                                        startup_config_path.display(),
+                                        fallback_config_path.display(),
                                         write_error
                                     );
                                 }
@@ -375,6 +417,8 @@ async fn run_telemt_core(
 
     let stats = Arc::new(Stats::new());
     stats.apply_telemetry_policy(TelemetryPolicy::from_config(&config.general.telemetry));
+    let quota_state_path = config.general.quota_state_path.clone();
+    crate::quota_state::load_quota_state(&quota_state_path, stats.as_ref()).await;
 
     let upstream_manager = Arc::new(UpstreamManager::new(
         config.upstreams.clone(),
@@ -454,6 +498,7 @@ async fn run_telemt_core(
             let config_rx_api = api_config_rx.clone();
             let admission_rx_api = admission_rx.clone();
             let config_path_api = config_path.clone();
+            let quota_state_path_api = quota_state_path.clone();
             let startup_tracker_api = startup_tracker.clone();
             let detected_ips_rx_api = detected_ips_rx.clone();
             tokio::spawn(async move {
@@ -467,6 +512,7 @@ async fn run_telemt_core(
                     config_rx_api,
                     admission_rx_api,
                     config_path_api,
+                    quota_state_path_api,
                     detected_ips_rx_api,
                     process_started_at_epoch_secs,
                     startup_tracker_api,
@@ -618,6 +664,8 @@ async fn run_telemt_core(
             .await;
     }
 
+    let (me_ready_tx, me_ready_rx) = watch::channel(0_u64);
+
     let me_pool: Option<Arc<MePool>> = me_startup::initialize_me_pool(
         use_middle_proxy,
         &config,
@@ -628,6 +676,7 @@ async fn run_telemt_core(
         rng.clone(),
         stats.clone(),
         api_me_pool.clone(),
+        me_ready_tx.clone(),
     )
     .await;
 
@@ -701,6 +750,7 @@ async fn run_telemt_core(
         api_config_tx.clone(),
         me_pool.clone(),
         shared_state.clone(),
+        me_ready_tx.clone(),
     )
     .await;
     let config_rx = runtime_watches.config_rx;
@@ -714,6 +764,7 @@ async fn run_telemt_core(
         route_runtime.clone(),
         &admission_tx,
         config_rx.clone(),
+        me_ready_rx,
     )
     .await;
     let _admission_tx_hold = admission_tx;
@@ -772,6 +823,7 @@ async fn run_telemt_core(
         beobachten.clone(),
         shared_state.clone(),
         ip_tracker.clone(),
+        tls_cache.clone(),
         config_rx.clone(),
     )
     .await;
@@ -799,7 +851,7 @@ async fn run_telemt_core(
         max_connections.clone(),
     );
 
-    shutdown::wait_for_shutdown(process_started_at, me_pool, stats).await;
+    shutdown::wait_for_shutdown(process_started_at, me_pool, stats, quota_state_path).await;
 
     Ok(())
 }

src/maestro/runtime_tasks.rs

@@ -21,6 +21,7 @@ use crate::startup::{
 use crate::stats::beobachten::BeobachtenStore;
 use crate::stats::telemetry::TelemetryPolicy;
 use crate::stats::{ReplayChecker, Stats};
+use crate::tls_front::TlsFrontCache;
 use crate::transport::UpstreamManager;
 use crate::transport::middle_proxy::{MePool, MeReinitTrigger};
 
@@ -52,6 +53,7 @@ pub(crate) async fn spawn_runtime_tasks(
     api_config_tx: watch::Sender<Arc<ProxyConfig>>,
     me_pool_for_policy: Option<Arc<MePool>>,
     shared_state: Arc<ProxySharedState>,
+    me_ready_tx: watch::Sender<u64>,
 ) -> RuntimeWatches {
     let um_clone = upstream_manager.clone();
     let dc_overrides_for_health = config.dc_overrides.clone();
@@ -249,12 +251,14 @@ pub(crate) async fn spawn_runtime_tasks(
         let pool_clone_sched = pool.clone();
         let rng_clone_sched = rng.clone();
         let config_rx_clone_sched = config_rx.clone();
+        let me_ready_tx_sched = me_ready_tx.clone();
         tokio::spawn(async move {
             crate::transport::middle_proxy::me_reinit_scheduler(
                 pool_clone_sched,
                 rng_clone_sched,
                 config_rx_clone_sched,
                 reinit_rx,
+                me_ready_tx_sched,
             )
             .await;
         });
@@ -328,6 +332,7 @@ pub(crate) async fn spawn_metrics_if_configured(
     beobachten: Arc<BeobachtenStore>,
     shared_state: Arc<ProxySharedState>,
     ip_tracker: Arc<UserIpTracker>,
+    tls_cache: Option<Arc<TlsFrontCache>>,
     config_rx: watch::Receiver<Arc<ProxyConfig>>,
 ) {
     // metrics_listen takes precedence; fall back to metrics_port for backward compat.
@@ -363,6 +368,7 @@ pub(crate) async fn spawn_metrics_if_configured(
         let shared_state = shared_state.clone();
         let config_rx_metrics = config_rx.clone();
         let ip_tracker_metrics = ip_tracker.clone();
+        let tls_cache_metrics = tls_cache.clone();
         let whitelist = config.server.metrics_whitelist.clone();
         let listen_backlog = config.server.listen_backlog;
         tokio::spawn(async move {
@@ -374,6 +380,7 @@ pub(crate) async fn spawn_metrics_if_configured(
                 beobachten,
                 shared_state,
                 ip_tracker_metrics,
+                tls_cache_metrics,
                 config_rx_metrics,
                 whitelist,
             )

src/maestro/shutdown.rs

@@ -9,6 +9,7 @@
 //! SIGHUP is handled separately in config/hot_reload.rs for config reload.
 
 use std::sync::Arc;
+use std::path::PathBuf;
 use std::time::{Duration, Instant};
 
 #[cfg(not(unix))]
@@ -48,9 +49,10 @@ pub(crate) async fn wait_for_shutdown(
     process_started_at: Instant,
     me_pool: Option<Arc<MePool>>,
     stats: Arc<Stats>,
+    quota_state_path: PathBuf,
 ) {
     let signal = wait_for_shutdown_signal().await;
-    perform_shutdown(signal, process_started_at, me_pool, &stats).await;
+    perform_shutdown(signal, process_started_at, me_pool, &stats, quota_state_path).await;
 }
 
 /// Waits for any shutdown signal (SIGINT, SIGTERM, SIGQUIT).
@@ -79,6 +81,7 @@ async fn perform_shutdown(
     process_started_at: Instant,
     me_pool: Option<Arc<MePool>>,
     stats: &Stats,
+    quota_state_path: PathBuf,
 ) {
     let shutdown_started_at = Instant::now();
     info!(signal = %signal, "Received shutdown signal");
@@ -109,6 +112,22 @@ async fn perform_shutdown(
         }
     }
 
+    match crate::quota_state::save_quota_state(&quota_state_path, stats).await {
+        Ok(()) => {
+            info!(
+                path = %quota_state_path.display(),
+                "Persisted per-user quota state"
+            );
+        }
+        Err(error) => {
+            warn!(
+                error = %error,
+                path = %quota_state_path.display(),
+                "Failed to persist per-user quota state"
+            );
+        }
+    }
+
     let shutdown_secs = shutdown_started_at.elapsed().as_secs();
     info!(
         "Shutdown completed successfully in {} {}.",

src/maestro/tls_bootstrap.rs

@@ -10,6 +10,14 @@ use crate::tls_front::TlsFrontCache;
 use crate::tls_front::fetcher::TlsFetchStrategy;
 use crate::transport::UpstreamManager;
 
+fn tls_fetch_host_for_domain(mask_host: &str, primary_tls_domain: &str, domain: &str) -> String {
+    if mask_host.eq_ignore_ascii_case(primary_tls_domain) {
+        domain.to_string()
+    } else {
+        mask_host.to_string()
+    }
+}
+
 pub(crate) async fn bootstrap_tls_front(
     config: &ProxyConfig,
     tls_domains: &[String],
@@ -56,6 +64,7 @@ pub(crate) async fn bootstrap_tls_front(
         let cache_initial = cache.clone();
         let domains_initial = tls_domains.to_vec();
         let host_initial = mask_host.clone();
+        let primary_initial = config.censorship.tls_domain.clone();
         let unix_sock_initial = mask_unix_sock.clone();
         let scope_initial = tls_fetch_scope.clone();
         let upstream_initial = upstream_manager.clone();
@@ -64,7 +73,8 @@ pub(crate) async fn bootstrap_tls_front(
             let mut join = tokio::task::JoinSet::new();
             for domain in domains_initial {
                 let cache_domain = cache_initial.clone();
-                let host_domain = host_initial.clone();
+                let host_domain =
+                    tls_fetch_host_for_domain(&host_initial, &primary_initial, &domain);
                 let unix_sock_domain = unix_sock_initial.clone();
                 let scope_domain = scope_initial.clone();
                 let upstream_domain = upstream_initial.clone();
@@ -117,6 +127,7 @@ pub(crate) async fn bootstrap_tls_front(
         let cache_refresh = cache.clone();
         let domains_refresh = tls_domains.to_vec();
         let host_refresh = mask_host.clone();
+        let primary_refresh = config.censorship.tls_domain.clone();
         let unix_sock_refresh = mask_unix_sock.clone();
         let scope_refresh = tls_fetch_scope.clone();
         let upstream_refresh = upstream_manager.clone();
@@ -130,7 +141,8 @@ pub(crate) async fn bootstrap_tls_front(
                 let mut join = tokio::task::JoinSet::new();
                 for domain in domains_refresh.clone() {
                     let cache_domain = cache_refresh.clone();
-                    let host_domain = host_refresh.clone();
+                    let host_domain =
+                        tls_fetch_host_for_domain(&host_refresh, &primary_refresh, &domain);
                     let unix_sock_domain = unix_sock_refresh.clone();
                     let scope_domain = scope_refresh.clone();
                     let upstream_domain = upstream_refresh.clone();
@@ -186,3 +198,24 @@ pub(crate) async fn bootstrap_tls_front(
 
     tls_cache
 }
+
+#[cfg(test)]
+mod tests {
+    use super::tls_fetch_host_for_domain;
+
+    #[test]
+    fn tls_fetch_host_uses_each_domain_when_mask_host_is_primary_default() {
+        assert_eq!(
+            tls_fetch_host_for_domain("a.com", "a.com", "b.com"),
+            "b.com"
+        );
+    }
+
+    #[test]
+    fn tls_fetch_host_preserves_explicit_non_primary_mask_host() {
+        assert_eq!(
+            tls_fetch_host_for_domain("origin.example", "a.com", "b.com"),
+            "origin.example"
+        );
+    }
+}

src/main.rs

@@ -25,6 +25,7 @@ mod metrics;
 mod network;
 mod protocol;
 mod proxy;
+mod quota_state;
 mod service;
 mod startup;
 mod stats;

src/metrics.rs

@@ -18,8 +18,16 @@ use crate::ip_tracker::UserIpTracker;
 use crate::proxy::shared_state::ProxySharedState;
 use crate::stats::Stats;
 use crate::stats::beobachten::BeobachtenStore;
+use crate::tls_front::TlsFrontCache;
+use crate::tls_front::cache;
+use crate::tls_front::fetcher;
 use crate::transport::{ListenOptions, create_listener};
 
+// Keeps `/metrics` response size bounded when per-user telemetry is enabled.
+const USER_LABELED_METRICS_MAX_USERS: usize = 4096;
+// Keeps TLS-front per-domain health series bounded for large generated configs.
+const TLS_FRONT_PROFILE_HEALTH_MAX_DOMAINS: usize = 256;
+
 pub async fn serve(
     port: u16,
     listen: Option<String>,
@@ -28,6 +36,7 @@ pub async fn serve(
     beobachten: Arc<BeobachtenStore>,
     shared_state: Arc<ProxySharedState>,
     ip_tracker: Arc<UserIpTracker>,
+    tls_cache: Option<Arc<TlsFrontCache>>,
     config_rx: tokio::sync::watch::Receiver<Arc<ProxyConfig>>,
     whitelist: Vec<IpNetwork>,
 ) {
@@ -52,6 +61,7 @@ pub async fn serve(
                     beobachten,
                     shared_state,
                     ip_tracker,
+                    tls_cache,
                     config_rx,
                     whitelist,
                 )
@@ -107,6 +117,7 @@ pub async fn serve(
                 beobachten,
                 shared_state,
                 ip_tracker,
+                tls_cache,
                 config_rx,
                 whitelist,
             )
@@ -117,6 +128,7 @@ pub async fn serve(
             let beobachten_v6 = beobachten.clone();
             let shared_state_v6 = shared_state.clone();
             let ip_tracker_v6 = ip_tracker.clone();
+            let tls_cache_v6 = tls_cache.clone();
             let config_rx_v6 = config_rx.clone();
             let whitelist_v6 = whitelist.clone();
             tokio::spawn(async move {
@@ -126,6 +138,7 @@ pub async fn serve(
                     beobachten_v6,
                     shared_state_v6,
                     ip_tracker_v6,
+                    tls_cache_v6,
                     config_rx_v6,
                     whitelist_v6,
                 )
@@ -137,6 +150,7 @@ pub async fn serve(
                 beobachten,
                 shared_state,
                 ip_tracker,
+                tls_cache,
                 config_rx,
                 whitelist,
             )
@@ -166,6 +180,7 @@ async fn serve_listener(
     beobachten: Arc<BeobachtenStore>,
     shared_state: Arc<ProxySharedState>,
     ip_tracker: Arc<UserIpTracker>,
+    tls_cache: Option<Arc<TlsFrontCache>>,
     config_rx: tokio::sync::watch::Receiver<Arc<ProxyConfig>>,
     whitelist: Arc<Vec<IpNetwork>>,
 ) {
@@ -187,6 +202,7 @@ async fn serve_listener(
         let beobachten = beobachten.clone();
         let shared_state = shared_state.clone();
         let ip_tracker = ip_tracker.clone();
+        let tls_cache = tls_cache.clone();
         let config_rx_conn = config_rx.clone();
         tokio::spawn(async move {
             let svc = service_fn(move |req| {
@@ -194,6 +210,7 @@ async fn serve_listener(
                 let beobachten = beobachten.clone();
                 let shared_state = shared_state.clone();
                 let ip_tracker = ip_tracker.clone();
+                let tls_cache = tls_cache.clone();
                 let config = config_rx_conn.borrow().clone();
                 async move {
                     handle(
@@ -202,6 +219,7 @@ async fn serve_listener(
                         &beobachten,
                         &shared_state,
                         &ip_tracker,
+                        tls_cache.as_deref(),
                         &config,
                     )
                     .await
@@ -223,10 +241,11 @@ async fn handle<B>(
     beobachten: &BeobachtenStore,
     shared_state: &ProxySharedState,
     ip_tracker: &UserIpTracker,
+    tls_cache: Option<&TlsFrontCache>,
     config: &ProxyConfig,
 ) -> Result<Response<Full<Bytes>>, Infallible> {
     if req.uri().path() == "/metrics" {
-        let body = render_metrics(stats, shared_state, config, ip_tracker).await;
+        let body = render_metrics(stats, shared_state, config, ip_tracker, tls_cache).await;
         let resp = Response::builder()
             .status(StatusCode::OK)
             .header("content-type", "text/plain; version=0.0.4; charset=utf-8")
@@ -261,11 +280,151 @@ fn render_beobachten(beobachten: &BeobachtenStore, config: &ProxyConfig) -> Stri
     beobachten.snapshot_text(ttl)
 }
 
+fn tls_front_domains(config: &ProxyConfig) -> Vec<String> {
+    let mut domains = Vec::with_capacity(1 + config.censorship.tls_domains.len());
+    if !config.censorship.tls_domain.is_empty() {
+        domains.push(config.censorship.tls_domain.clone());
+    }
+    for domain in &config.censorship.tls_domains {
+        if !domain.is_empty() && !domains.contains(domain) {
+            domains.push(domain.clone());
+        }
+    }
+    domains
+}
+
+fn prometheus_label_value(value: &str) -> String {
+    value.replace('\\', "\\\\").replace('"', "\\\"")
+}
+
+async fn render_tls_front_profile_health(
+    out: &mut String,
+    config: &ProxyConfig,
+    tls_cache: Option<&TlsFrontCache>,
+) {
+    use std::fmt::Write;
+
+    let domains = tls_front_domains(config);
+    let (health, suppressed) = match (config.censorship.tls_emulation, tls_cache) {
+        (true, Some(cache)) => {
+            cache
+                .profile_health_snapshot(&domains, TLS_FRONT_PROFILE_HEALTH_MAX_DOMAINS)
+                .await
+        }
+        _ => (Vec::new(), domains.len()),
+    };
+
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_profile_domains TLS front configured profile domains by export status"
+    );
+    let _ = writeln!(out, "# TYPE telemt_tls_front_profile_domains gauge");
+    let _ = writeln!(
+        out,
+        "telemt_tls_front_profile_domains{{status=\"configured\"}} {}",
+        domains.len()
+    );
+    let _ = writeln!(
+        out,
+        "telemt_tls_front_profile_domains{{status=\"emitted\"}} {}",
+        health.len()
+    );
+    let _ = writeln!(
+        out,
+        "telemt_tls_front_profile_domains{{status=\"suppressed\"}} {}",
+        suppressed
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_profile_info TLS front profile source and feature flags per configured domain"
+    );
+    let _ = writeln!(out, "# TYPE telemt_tls_front_profile_info gauge");
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_profile_age_seconds Age of cached TLS front profile data per configured domain"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_tls_front_profile_age_seconds gauge"
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_profile_app_data_records TLS front cached app-data record count per configured domain"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_tls_front_profile_app_data_records gauge"
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_profile_ticket_records TLS front cached ticket-like tail record count per configured domain"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_tls_front_profile_ticket_records gauge"
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_profile_change_cipher_spec_records TLS front cached ChangeCipherSpec record count per configured domain"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_tls_front_profile_change_cipher_spec_records gauge"
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_profile_app_data_bytes TLS front cached total app-data bytes per configured domain"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_tls_front_profile_app_data_bytes gauge"
+    );
+
+    for item in health {
+        let domain = prometheus_label_value(&item.domain);
+        let _ = writeln!(
+            out,
+            "telemt_tls_front_profile_info{{domain=\"{}\",source=\"{}\",is_default=\"{}\",has_cert_info=\"{}\",has_cert_payload=\"{}\"}} 1",
+            domain,
+            item.source,
+            item.is_default,
+            item.has_cert_info,
+            item.has_cert_payload
+        );
+        let _ = writeln!(
+            out,
+            "telemt_tls_front_profile_age_seconds{{domain=\"{}\"}} {}",
+            domain, item.age_seconds
+        );
+        let _ = writeln!(
+            out,
+            "telemt_tls_front_profile_app_data_records{{domain=\"{}\"}} {}",
+            domain, item.app_data_records
+        );
+        let _ = writeln!(
+            out,
+            "telemt_tls_front_profile_ticket_records{{domain=\"{}\"}} {}",
+            domain, item.ticket_records
+        );
+        let _ = writeln!(
+            out,
+            "telemt_tls_front_profile_change_cipher_spec_records{{domain=\"{}\"}} {}",
+            domain, item.change_cipher_spec_count
+        );
+        let _ = writeln!(
+            out,
+            "telemt_tls_front_profile_app_data_bytes{{domain=\"{}\"}} {}",
+            domain, item.total_app_data_len
+        );
+    }
+}
+
 async fn render_metrics(
     stats: &Stats,
     shared_state: &ProxySharedState,
     config: &ProxyConfig,
     ip_tracker: &UserIpTracker,
+    tls_cache: Option<&TlsFrontCache>,
 ) -> String {
     use std::fmt::Write;
     let mut out = String::with_capacity(4096);
@@ -311,6 +470,12 @@ async fn render_metrics(
         "telemt_telemetry_user_enabled {}",
         if user_enabled { 1 } else { 0 }
     );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_stats_user_entries Retained per-user stats entries"
+    );
+    let _ = writeln!(out, "# TYPE telemt_stats_user_entries gauge");
+    let _ = writeln!(out, "telemt_stats_user_entries {}", stats.user_stats_len());
 
     let _ = writeln!(
         out,
@@ -366,6 +531,54 @@ async fn render_metrics(
         stats.get_buffer_pool_in_use_gauge()
     );
 
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_fetch_profile_cache_entries Current adaptive TLS fetch profile-cache entries"
+    );
+    let _ = writeln!(out, "# TYPE telemt_tls_fetch_profile_cache_entries gauge");
+    let _ = writeln!(
+        out,
+        "telemt_tls_fetch_profile_cache_entries {}",
+        fetcher::profile_cache_entries_for_metrics()
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_fetch_profile_cache_cap_drops_total Profile-cache winner inserts skipped because the cache cap was reached"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_tls_fetch_profile_cache_cap_drops_total counter"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_tls_fetch_profile_cache_cap_drops_total {}",
+        fetcher::profile_cache_cap_drops_for_metrics()
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_full_cert_budget_ips Current IP entries tracked by TLS full-cert budget"
+    );
+    let _ = writeln!(out, "# TYPE telemt_tls_front_full_cert_budget_ips gauge");
+    let _ = writeln!(
+        out,
+        "telemt_tls_front_full_cert_budget_ips {}",
+        cache::full_cert_sent_ips_for_metrics()
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_tls_front_full_cert_budget_cap_drops_total New IPs denied full-cert budget tracking because the cap was reached"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_tls_front_full_cert_budget_cap_drops_total counter"
+    );
+    let _ = writeln!(
+        out,
+        "telemt_tls_front_full_cert_budget_cap_drops_total {}",
+        cache::full_cert_sent_cap_drops_for_metrics()
+    );
+    render_tls_front_profile_health(&mut out, config, tls_cache).await;
+
     let _ = writeln!(
         out,
         "# HELP telemt_connections_total Total accepted connections"
@@ -396,6 +609,21 @@ async fn render_metrics(
         }
     );
 
+    let _ = writeln!(
+        out,
+        "# HELP telemt_connections_bad_by_class_total Bad/rejected connections by class"
+    );
+    let _ = writeln!(out, "# TYPE telemt_connections_bad_by_class_total counter");
+    if core_enabled {
+        for (class, total) in stats.get_connects_bad_class_counts() {
+            let _ = writeln!(
+                out,
+                "telemt_connections_bad_by_class_total{{class=\"{}\"}} {}",
+                class, total
+            );
+        }
+    }
+
     let _ = writeln!(
         out,
         "# HELP telemt_handshake_timeouts_total Handshake timeouts"
@@ -411,6 +639,24 @@ async fn render_metrics(
         }
     );
 
+    let _ = writeln!(
+        out,
+        "# HELP telemt_handshake_failures_by_class_total Handshake failures by class"
+    );
+    let _ = writeln!(
+        out,
+        "# TYPE telemt_handshake_failures_by_class_total counter"
+    );
+    if core_enabled {
+        for (class, total) in stats.get_handshake_failure_class_counts() {
+            let _ = writeln!(
+                out,
+                "telemt_handshake_failures_by_class_total{{class=\"{}\"}} {}",
+                class, total
+            );
+        }
+    }
+
     let _ = writeln!(
         out,
         "# HELP telemt_auth_expensive_checks_total Expensive authentication candidate checks executed during handshake validation"
@@ -3019,17 +3265,6 @@ async fn render_metrics(
             0
         }
     );
-    let _ = writeln!(
-        out,
-        "# HELP telemt_telemetry_user_series_suppressed User-labeled metric series suppression flag"
-    );
-    let _ = writeln!(out, "# TYPE telemt_telemetry_user_series_suppressed gauge");
-    let _ = writeln!(
-        out,
-        "telemt_telemetry_user_series_suppressed {}",
-        if user_enabled { 0 } else { 1 }
-    );
-
     let ip_memory = ip_tracker.memory_stats().await;
     let _ = writeln!(
         out,
@@ -3071,11 +3306,46 @@ async fn render_metrics(
         "telemt_ip_tracker_cleanup_queue_len {}",
         ip_memory.cleanup_queue_len
     );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_ip_tracker_cleanup_total Release cleanups deferred through the cleanup queue"
+    );
+    let _ = writeln!(out, "# TYPE telemt_ip_tracker_cleanup_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_ip_tracker_cleanup_total{{path=\"deferred\"}} {}",
+        ip_memory.cleanup_deferred_releases
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_ip_tracker_cap_rejects_total New connection rejects caused by global IP tracker caps"
+    );
+    let _ = writeln!(out, "# TYPE telemt_ip_tracker_cap_rejects_total counter");
+    let _ = writeln!(
+        out,
+        "telemt_ip_tracker_cap_rejects_total{{scope=\"active\"}} {}",
+        ip_memory.active_cap_rejects
+    );
+    let _ = writeln!(
+        out,
+        "telemt_ip_tracker_cap_rejects_total{{scope=\"recent\"}} {}",
+        ip_memory.recent_cap_rejects
+    );
+
+    let mut user_stats_emitted = 0usize;
+    let mut user_stats_suppressed = 0usize;
+    let mut unique_ip_emitted = 0usize;
+    let mut unique_ip_suppressed = 0usize;
 
     if user_enabled {
         for entry in stats.iter_user_stats() {
+            if user_stats_emitted >= USER_LABELED_METRICS_MAX_USERS {
+                user_stats_suppressed = user_stats_suppressed.saturating_add(1);
+                continue;
+            }
             let user = entry.key();
             let s = entry.value();
+            user_stats_emitted = user_stats_emitted.saturating_add(1);
             let _ = writeln!(
                 out,
                 "telemt_user_connections_total{{user=\"{}\"}} {}",
@@ -3117,7 +3387,7 @@ async fn render_metrics(
             );
         }
 
-        let ip_stats = ip_tracker.get_stats().await;
+        let ip_stats = ip_tracker.get_stats_snapshot().await;
         let ip_counts: HashMap<String, usize> = ip_stats
             .into_iter()
             .map(|(user, count, _)| (user, count))
@@ -3129,7 +3399,7 @@ async fn render_metrics(
         unique_users.extend(ip_counts.keys().cloned());
         let unique_users_vec: Vec<String> = unique_users.iter().cloned().collect();
         let recent_counts = ip_tracker
-            .get_recent_counts_for_users(&unique_users_vec)
+            .get_recent_counts_for_users_snapshot(&unique_users_vec)
             .await;
 
         let _ = writeln!(
@@ -3154,6 +3424,11 @@ async fn render_metrics(
         let _ = writeln!(out, "# TYPE telemt_user_unique_ips_utilization gauge");
 
         for user in unique_users {
+            if unique_ip_emitted >= USER_LABELED_METRICS_MAX_USERS {
+                unique_ip_suppressed = unique_ip_suppressed.saturating_add(1);
+                continue;
+            }
+            unique_ip_emitted = unique_ip_emitted.saturating_add(1);
             let current = ip_counts.get(&user).copied().unwrap_or(0);
             let limit = config
                 .access
@@ -3193,6 +3468,46 @@ async fn render_metrics(
         }
     }
 
+    let _ = writeln!(
+        out,
+        "# HELP telemt_telemetry_user_series_suppressed User-labeled metric series suppression flag"
+    );
+    let _ = writeln!(out, "# TYPE telemt_telemetry_user_series_suppressed gauge");
+    let _ = writeln!(
+        out,
+        "telemt_telemetry_user_series_suppressed {}",
+        if user_enabled && user_stats_suppressed == 0 && unique_ip_suppressed == 0 {
+            0
+        } else {
+            1
+        }
+    );
+    let _ = writeln!(
+        out,
+        "# HELP telemt_telemetry_user_series_users User-labeled metric users by export status"
+    );
+    let _ = writeln!(out, "# TYPE telemt_telemetry_user_series_users gauge");
+    let _ = writeln!(
+        out,
+        "telemt_telemetry_user_series_users{{family=\"stats\",status=\"emitted\"}} {}",
+        user_stats_emitted
+    );
+    let _ = writeln!(
+        out,
+        "telemt_telemetry_user_series_users{{family=\"stats\",status=\"suppressed\"}} {}",
+        user_stats_suppressed
+    );
+    let _ = writeln!(
+        out,
+        "telemt_telemetry_user_series_users{{family=\"unique_ip\",status=\"emitted\"}} {}",
+        unique_ip_emitted
+    );
+    let _ = writeln!(
+        out,
+        "telemt_telemetry_user_series_users{{family=\"unique_ip\",status=\"suppressed\"}} {}",
+        unique_ip_suppressed
+    );
+
     out
 }
 
@@ -3201,6 +3516,11 @@ mod tests {
     use super::*;
     use http_body_util::BodyExt;
     use std::net::IpAddr;
+    use std::time::SystemTime;
+
+    use crate::tls_front::types::{
+        CachedTlsData, ParsedServerHello, TlsBehaviorProfile, TlsCertPayload, TlsProfileSource,
+    };
 
     #[tokio::test]
     async fn test_render_metrics_format() {
@@ -3215,8 +3535,9 @@ mod tests {
 
         stats.increment_connects_all();
         stats.increment_connects_all();
-        stats.increment_connects_bad();
+        stats.increment_connects_bad_with_class("tls_handshake_bad_client");
         stats.increment_handshake_timeouts();
+        stats.increment_handshake_failure_class("timeout");
         shared_state
             .handshake
             .auth_expensive_checks_total
@@ -3268,7 +3589,7 @@ mod tests {
             .await
             .unwrap();
 
-        let output = render_metrics(&stats, shared_state.as_ref(), &config, &tracker).await;
+        let output = render_metrics(&stats, shared_state.as_ref(), &config, &tracker, None).await;
 
         assert!(output.contains(&format!(
             "telemt_build_info{{version=\"{}\"}} 1",
@@ -3276,7 +3597,10 @@ mod tests {
         )));
         assert!(output.contains("telemt_connections_total 2"));
         assert!(output.contains("telemt_connections_bad_total 1"));
+        assert!(output
+            .contains("telemt_connections_bad_by_class_total{class=\"tls_handshake_bad_client\"} 1"));
         assert!(output.contains("telemt_handshake_timeouts_total 1"));
+        assert!(output.contains("telemt_handshake_failures_by_class_total{class=\"timeout\"} 1"));
         assert!(output.contains("telemt_auth_expensive_checks_total 9"));
         assert!(output.contains("telemt_auth_budget_exhausted_total 2"));
         assert!(output.contains("telemt_upstream_connect_attempt_total 2"));
@@ -3330,13 +3654,86 @@ mod tests {
         assert!(output.contains("telemt_ip_tracker_cleanup_queue_len 0"));
     }
 
+    #[tokio::test]
+    async fn test_render_tls_front_profile_health() {
+        let stats = Stats::new();
+        let shared_state = ProxySharedState::new();
+        let tracker = UserIpTracker::new();
+        let mut config = ProxyConfig::default();
+        config.censorship.tls_domain = "primary.example".to_string();
+        config.censorship.tls_domains = vec!["fallback.example".to_string()];
+
+        let cache = TlsFrontCache::new(
+            &[
+                "primary.example".to_string(),
+                "fallback.example".to_string(),
+            ],
+            1024,
+            "tlsfront-profile-health-test",
+        );
+        cache
+            .set(
+                "primary.example",
+                CachedTlsData {
+                    server_hello_template: ParsedServerHello {
+                        version: [0x03, 0x03],
+                        random: [0u8; 32],
+                        session_id: Vec::new(),
+                        cipher_suite: [0x13, 0x01],
+                        compression: 0,
+                        extensions: Vec::new(),
+                    },
+                    cert_info: None,
+                    cert_payload: Some(TlsCertPayload {
+                        cert_chain_der: vec![vec![0x30, 0x01]],
+                        certificate_message: vec![0x0b, 0x00, 0x00, 0x00],
+                    }),
+                    app_data_records_sizes: vec![1024, 512],
+                    total_app_data_len: 1536,
+                    behavior_profile: TlsBehaviorProfile {
+                        change_cipher_spec_count: 1,
+                        app_data_record_sizes: vec![1024, 512],
+                        ticket_record_sizes: vec![69],
+                        source: TlsProfileSource::Merged,
+                    },
+                    fetched_at: SystemTime::now(),
+                    domain: "primary.example".to_string(),
+                },
+            )
+            .await;
+
+        let output = render_metrics(&stats, &shared_state, &config, &tracker, Some(&cache)).await;
+
+        assert!(output.contains("telemt_tls_front_profile_domains{status=\"configured\"} 2"));
+        assert!(output.contains("telemt_tls_front_profile_domains{status=\"emitted\"} 2"));
+        assert!(output.contains("telemt_tls_front_profile_domains{status=\"suppressed\"} 0"));
+        assert!(
+            output.contains("telemt_tls_front_profile_info{domain=\"primary.example\",source=\"merged\",is_default=\"false\",has_cert_info=\"false\",has_cert_payload=\"true\"} 1")
+        );
+        assert!(
+            output.contains("telemt_tls_front_profile_info{domain=\"fallback.example\",source=\"default\",is_default=\"true\",has_cert_info=\"false\",has_cert_payload=\"false\"} 1")
+        );
+        assert!(
+            output.contains("telemt_tls_front_profile_app_data_records{domain=\"primary.example\"} 2")
+        );
+        assert!(
+            output.contains("telemt_tls_front_profile_ticket_records{domain=\"primary.example\"} 1")
+        );
+        assert!(
+            output.contains("telemt_tls_front_profile_change_cipher_spec_records{domain=\"primary.example\"} 1")
+        );
+        assert!(
+            output.contains("telemt_tls_front_profile_app_data_bytes{domain=\"primary.example\"} 1536")
+        );
+    }
+
     #[tokio::test]
     async fn test_render_empty_stats() {
         let stats = Stats::new();
         let shared_state = ProxySharedState::new();
         let tracker = UserIpTracker::new();
         let config = ProxyConfig::default();
-        let output = render_metrics(&stats, &shared_state, &config, &tracker).await;
+        let output = render_metrics(&stats, &shared_state, &config, &tracker, None).await;
         assert!(output.contains("telemt_connections_total 0"));
         assert!(output.contains("telemt_connections_bad_total 0"));
         assert!(output.contains("telemt_handshake_timeouts_total 0"));
@@ -3360,7 +3757,7 @@ mod tests {
         let mut config = ProxyConfig::default();
         config.access.user_max_unique_ips_global_each = 2;
 
-        let output = render_metrics(&stats, &shared_state, &config, &tracker).await;
+        let output = render_metrics(&stats, &shared_state, &config, &tracker, None).await;
 
         assert!(output.contains("telemt_user_unique_ips_limit{user=\"alice\"} 2"));
         assert!(output.contains("telemt_user_unique_ips_utilization{user=\"alice\"} 0.500000"));
@@ -3372,11 +3769,13 @@ mod tests {
         let shared_state = ProxySharedState::new();
         let tracker = UserIpTracker::new();
         let config = ProxyConfig::default();
-        let output = render_metrics(&stats, &shared_state, &config, &tracker).await;
+        let output = render_metrics(&stats, &shared_state, &config, &tracker, None).await;
         assert!(output.contains("# TYPE telemt_uptime_seconds gauge"));
         assert!(output.contains("# TYPE telemt_connections_total counter"));
         assert!(output.contains("# TYPE telemt_connections_bad_total counter"));
+        assert!(output.contains("# TYPE telemt_connections_bad_by_class_total counter"));
         assert!(output.contains("# TYPE telemt_handshake_timeouts_total counter"));
+        assert!(output.contains("# TYPE telemt_handshake_failures_by_class_total counter"));
         assert!(output.contains("# TYPE telemt_auth_expensive_checks_total counter"));
         assert!(output.contains("# TYPE telemt_auth_budget_exhausted_total counter"));
         assert!(output.contains("# TYPE telemt_upstream_connect_attempt_total counter"));
@@ -3406,9 +3805,28 @@ mod tests {
         assert!(output.contains("# TYPE telemt_user_unique_ips_recent_window gauge"));
         assert!(output.contains("# TYPE telemt_user_unique_ips_limit gauge"));
         assert!(output.contains("# TYPE telemt_user_unique_ips_utilization gauge"));
+        assert!(output.contains("# TYPE telemt_stats_user_entries gauge"));
+        assert!(output.contains("# TYPE telemt_telemetry_user_series_users gauge"));
         assert!(output.contains("# TYPE telemt_ip_tracker_users gauge"));
         assert!(output.contains("# TYPE telemt_ip_tracker_entries gauge"));
         assert!(output.contains("# TYPE telemt_ip_tracker_cleanup_queue_len gauge"));
+        assert!(output.contains("# TYPE telemt_ip_tracker_cleanup_total counter"));
+        assert!(output.contains("# TYPE telemt_ip_tracker_cap_rejects_total counter"));
+        assert!(output.contains("# TYPE telemt_tls_fetch_profile_cache_entries gauge"));
+        assert!(output.contains("# TYPE telemt_tls_fetch_profile_cache_cap_drops_total counter"));
+        assert!(output.contains("# TYPE telemt_tls_front_full_cert_budget_ips gauge"));
+        assert!(
+            output.contains("# TYPE telemt_tls_front_full_cert_budget_cap_drops_total counter")
+        );
+        assert!(output.contains("# TYPE telemt_tls_front_profile_domains gauge"));
+        assert!(output.contains("# TYPE telemt_tls_front_profile_info gauge"));
+        assert!(output.contains("# TYPE telemt_tls_front_profile_age_seconds gauge"));
+        assert!(output.contains("# TYPE telemt_tls_front_profile_app_data_records gauge"));
+        assert!(output.contains("# TYPE telemt_tls_front_profile_ticket_records gauge"));
+        assert!(
+            output.contains("# TYPE telemt_tls_front_profile_change_cipher_spec_records gauge")
+        );
+        assert!(output.contains("# TYPE telemt_tls_front_profile_app_data_bytes gauge"));
     }
 
     #[tokio::test]
@@ -3429,6 +3847,7 @@ mod tests {
             &beobachten,
             shared_state.as_ref(),
             &tracker,
+            None,
             &config,
         )
         .await
@@ -3463,6 +3882,7 @@ mod tests {
             &beobachten,
             shared_state.as_ref(),
             &tracker,
+            None,
             &config,
         )
         .await
@@ -3480,6 +3900,7 @@ mod tests {
             &beobachten,
             shared_state.as_ref(),
             &tracker,
+            None,
             &config,
         )
         .await

src/proxy/client.rs

@@ -1431,8 +1431,8 @@ impl RunningClientHandler {
 
     /// Main dispatch after successful handshake.
     /// Two modes:
-    ///   - Direct: TCP relay to TG DC (existing behavior)  
-    ///   - Middle Proxy: RPC multiplex through ME pool (new — supports CDN DCs)
+    ///   - Direct: TCP relay to TG DC (existing behavior)
+    ///   - Middle Proxy: RPC multiplex through ME pool (supports CDN DCs)
     #[cfg(test)]
     async fn handle_authenticated_static<R, W>(
         client_reader: CryptoReader<R>,

src/proxy/handshake.rs

@@ -1450,6 +1450,20 @@ where
         validated_secret.copy_from_slice(secret);
     }
 
+    if config
+        .access
+        .is_user_source_ip_denied(validated_user.as_str(), peer.ip())
+    {
+        auth_probe_record_failure_in(shared, peer.ip(), Instant::now());
+        maybe_apply_server_hello_delay(config).await;
+        warn!(
+            peer = %peer,
+            user = %validated_user,
+            "TLS handshake rejected: client source IP on per-user deny list (access.user_source_deny)"
+        );
+        return HandshakeResult::BadClient { reader, writer };
+    }
+
     // Reject known replay digests before expensive cache/domain/ALPN policy work.
     let digest_half = &validation_digest[..tls::TLS_DIGEST_HALF_LEN];
     if replay_checker.check_tls_digest(digest_half) {
@@ -1795,6 +1809,20 @@ where
 
         let validation = matched_validation.expect("validation must exist when matched");
 
+        if config
+            .access
+            .is_user_source_ip_denied(matched_user.as_str(), peer.ip())
+        {
+            auth_probe_record_failure_in(shared, peer.ip(), Instant::now());
+            maybe_apply_server_hello_delay(config).await;
+            warn!(
+                peer = %peer,
+                user = %matched_user,
+                "MTProto handshake rejected: client source IP on per-user deny list (access.user_source_deny)"
+            );
+            return HandshakeResult::BadClient { reader, writer };
+        }
+
         // Apply replay tracking only after successful authentication.
         //
         // This ordering prevents an attacker from producing invalid handshakes that
@@ -1873,6 +1901,17 @@ where
                 .auth_expensive_checks_total
                 .fetch_add(validation_checks as u64, Ordering::Relaxed);
 
+            if config.access.is_user_source_ip_denied(user.as_str(), peer.ip()) {
+                auth_probe_record_failure_in(shared, peer.ip(), Instant::now());
+                maybe_apply_server_hello_delay(config).await;
+                warn!(
+                    peer = %peer,
+                    user = %user,
+                    "MTProto handshake rejected: client source IP on per-user deny list (access.user_source_deny)"
+                );
+                return HandshakeResult::BadClient { reader, writer };
+            }
+
             // Apply replay tracking only after successful authentication.
             //
             // This ordering prevents an attacker from producing invalid handshakes that

src/proxy/masking.rs

@@ -2,6 +2,7 @@
 
 use crate::config::ProxyConfig;
 use crate::network::dns_overrides::resolve_socket_addr;
+use crate::protocol::tls;
 use crate::stats::beobachten::BeobachtenStore;
 use crate::transport::proxy_protocol::{ProxyProtocolV1Builder, ProxyProtocolV2Builder};
 #[cfg(unix)]
@@ -328,6 +329,89 @@ async fn wait_mask_outcome_budget(started: Instant, config: &ProxyConfig) {
     }
 }
 
+#[cfg(test)]
+mod tls_domain_mask_host_tests {
+    use super::{mask_host_for_initial_data, matching_tls_domain_for_sni};
+    use crate::config::ProxyConfig;
+
+    fn client_hello_with_sni(sni_host: &str) -> Vec<u8> {
+        let mut body = Vec::new();
+        body.extend_from_slice(&[0x03, 0x03]);
+        body.extend_from_slice(&[0u8; 32]);
+        body.push(32);
+        body.extend_from_slice(&[0x42u8; 32]);
+        body.extend_from_slice(&2u16.to_be_bytes());
+        body.extend_from_slice(&[0x13, 0x01]);
+        body.push(1);
+        body.push(0);
+
+        let host_bytes = sni_host.as_bytes();
+        let mut sni_payload = Vec::new();
+        sni_payload.extend_from_slice(&((host_bytes.len() + 3) as u16).to_be_bytes());
+        sni_payload.push(0);
+        sni_payload.extend_from_slice(&(host_bytes.len() as u16).to_be_bytes());
+        sni_payload.extend_from_slice(host_bytes);
+
+        let mut extensions = Vec::new();
+        extensions.extend_from_slice(&0x0000u16.to_be_bytes());
+        extensions.extend_from_slice(&(sni_payload.len() as u16).to_be_bytes());
+        extensions.extend_from_slice(&sni_payload);
+        body.extend_from_slice(&(extensions.len() as u16).to_be_bytes());
+        body.extend_from_slice(&extensions);
+
+        let mut handshake = Vec::new();
+        handshake.push(0x01);
+        let body_len = (body.len() as u32).to_be_bytes();
+        handshake.extend_from_slice(&body_len[1..4]);
+        handshake.extend_from_slice(&body);
+
+        let mut record = Vec::new();
+        record.push(0x16);
+        record.extend_from_slice(&[0x03, 0x01]);
+        record.extend_from_slice(&(handshake.len() as u16).to_be_bytes());
+        record.extend_from_slice(&handshake);
+        record
+    }
+
+    fn config_with_tls_domains() -> ProxyConfig {
+        let mut config = ProxyConfig::default();
+        config.censorship.tls_domain = "a.com".to_string();
+        config.censorship.tls_domains = vec!["b.com".to_string(), "c.com".to_string()];
+        config.censorship.mask_host = Some("a.com".to_string());
+        config
+    }
+
+    #[test]
+    fn matching_tls_domain_accepts_primary_and_extra_domains_case_insensitively() {
+        let config = config_with_tls_domains();
+
+        assert_eq!(matching_tls_domain_for_sni(&config, "A.COM"), Some("a.com"));
+        assert_eq!(matching_tls_domain_for_sni(&config, "B.COM"), Some("b.com"));
+        assert_eq!(matching_tls_domain_for_sni(&config, "unknown.com"), None);
+    }
+
+    #[test]
+    fn mask_host_preserves_explicit_non_primary_origin() {
+        let mut config = config_with_tls_domains();
+        config.censorship.mask_host = Some("origin.example".to_string());
+
+        let initial_data = client_hello_with_sni("b.com");
+
+        assert_eq!(
+            mask_host_for_initial_data(&config, &initial_data),
+            "origin.example"
+        );
+    }
+
+    #[test]
+    fn mask_host_uses_matching_tls_domain_when_mask_host_is_primary_default() {
+        let config = config_with_tls_domains();
+        let initial_data = client_hello_with_sni("b.com");
+
+        assert_eq!(mask_host_for_initial_data(&config, &initial_data), "b.com");
+    }
+}
+
 /// Detect client type based on initial data
 fn detect_client_type(data: &[u8]) -> &'static str {
     // Check for HTTP request
@@ -360,6 +444,37 @@ fn parse_mask_host_ip_literal(host: &str) -> Option<IpAddr> {
     host.parse::<IpAddr>().ok()
 }
 
+fn matching_tls_domain_for_sni<'a>(config: &'a ProxyConfig, sni: &str) -> Option<&'a str> {
+    if config.censorship.tls_domain.eq_ignore_ascii_case(sni) {
+        return Some(config.censorship.tls_domain.as_str());
+    }
+
+    for domain in &config.censorship.tls_domains {
+        if domain.eq_ignore_ascii_case(sni) {
+            return Some(domain.as_str());
+        }
+    }
+
+    None
+}
+
+fn mask_host_for_initial_data<'a>(config: &'a ProxyConfig, initial_data: &[u8]) -> &'a str {
+    let configured_mask_host = config
+        .censorship
+        .mask_host
+        .as_deref()
+        .unwrap_or(&config.censorship.tls_domain);
+
+    if !configured_mask_host.eq_ignore_ascii_case(&config.censorship.tls_domain) {
+        return configured_mask_host;
+    }
+
+    tls::extract_sni_from_client_hello(initial_data)
+        .as_deref()
+        .and_then(|sni| matching_tls_domain_for_sni(config, sni))
+        .unwrap_or(configured_mask_host)
+}
+
 fn canonical_ip(ip: IpAddr) -> IpAddr {
     match ip {
         IpAddr::V6(v6) => v6
@@ -734,11 +849,7 @@ pub async fn handle_bad_client<R, W>(
         return;
     }
 
-    let mask_host = config
-        .censorship
-        .mask_host
-        .as_deref()
-        .unwrap_or(&config.censorship.tls_domain);
+    let mask_host = mask_host_for_initial_data(config, initial_data);
     let mask_port = config.censorship.mask_port;
 
     // Fail closed when fallback points at our own listener endpoint.

src/proxy/tests/direct_relay_security_tests.rs

@@ -669,6 +669,13 @@ fn adversarial_check_then_symlink_flip_is_blocked_by_nofollow_open() {
             "telemt-unknown-dc-check-open-race-{}",
             std::process::id()
         ));
+    if let Ok(meta) = fs::symlink_metadata(&parent) {
+        if meta.file_type().is_symlink() || meta.is_file() {
+            fs::remove_file(&parent).expect("stale check-open-race path must be removable");
+        } else {
+            fs::remove_dir_all(&parent).expect("stale check-open-race parent must be removable");
+        }
+    }
     fs::create_dir_all(&parent).expect("check-open-race parent must be creatable");
 
     let target = parent.join("unknown-dc.log");

src/quota_state.rs

@@ -0,0 +1,114 @@
+use std::collections::BTreeMap;
+use std::path::Path;
+use std::time::{SystemTime, UNIX_EPOCH};
+
+use serde::{Deserialize, Serialize};
+use tokio::io::AsyncWriteExt;
+use tracing::{info, warn};
+
+use crate::stats::{Stats, UserQuotaSnapshot};
+
+#[derive(Debug, Default, Serialize, Deserialize)]
+pub(crate) struct QuotaStateFile {
+    pub(crate) last_reset_epoch_secs: u64,
+    pub(crate) users: BTreeMap<String, QuotaUserState>,
+}
+
+#[derive(Debug, Default, Serialize, Deserialize)]
+pub(crate) struct QuotaUserState {
+    pub(crate) used_bytes: u64,
+    pub(crate) last_reset_epoch_secs: u64,
+}
+
+fn now_epoch_secs() -> u64 {
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_secs()
+}
+
+pub(crate) async fn load_quota_state(path: &Path, stats: &Stats) {
+    let bytes = match tokio::fs::read(path).await {
+        Ok(bytes) => bytes,
+        Err(error) if error.kind() == std::io::ErrorKind::NotFound => return,
+        Err(error) => {
+            warn!(
+                error = %error,
+                path = %path.display(),
+                "Failed to read quota state file"
+            );
+            return;
+        }
+    };
+
+    let state = match serde_json::from_slice::<QuotaStateFile>(&bytes) {
+        Ok(state) => state,
+        Err(error) => {
+            warn!(
+                error = %error,
+                path = %path.display(),
+                "Failed to parse quota state file"
+            );
+            return;
+        }
+    };
+
+    let loaded_users = state.users.len();
+    for (user, quota) in state.users {
+        stats.load_user_quota_state(&user, quota.used_bytes, quota.last_reset_epoch_secs);
+    }
+    info!(
+        path = %path.display(),
+        loaded_users,
+        "Loaded per-user quota state"
+    );
+}
+
+pub(crate) async fn save_quota_state(path: &Path, stats: &Stats) -> std::io::Result<()> {
+    let mut users = BTreeMap::new();
+    let mut last_reset_epoch_secs = 0;
+    for (user, quota) in stats.user_quota_snapshot() {
+        last_reset_epoch_secs = last_reset_epoch_secs.max(quota.last_reset_epoch_secs);
+        users.insert(user, quota_user_state(quota));
+    }
+
+    let state = QuotaStateFile {
+        last_reset_epoch_secs,
+        users,
+    };
+    write_state_file(path, &state).await
+}
+
+pub(crate) async fn reset_user_quota(
+    path: &Path,
+    stats: &Stats,
+    user: &str,
+) -> std::io::Result<UserQuotaSnapshot> {
+    let snapshot = stats.reset_user_quota(user);
+    save_quota_state(path, stats).await?;
+    Ok(snapshot)
+}
+
+async fn write_state_file(path: &Path, state: &QuotaStateFile) -> std::io::Result<()> {
+    if let Some(parent) = path.parent()
+        && !parent.as_os_str().is_empty()
+    {
+        tokio::fs::create_dir_all(parent).await?;
+    }
+
+    let tmp_path = path.with_extension(format!("tmp.{}", now_epoch_secs()));
+    let payload = serde_json::to_vec_pretty(state)?;
+    let mut file = tokio::fs::File::create(&tmp_path).await?;
+    file.write_all(&payload).await?;
+    file.write_all(b"\n").await?;
+    file.sync_all().await?;
+    drop(file);
+    tokio::fs::rename(&tmp_path, path).await
+}
+
+fn quota_user_state(quota: UserQuotaSnapshot) -> QuotaUserState {
+    QuotaUserState {
+        used_bytes: quota.used_bytes,
+        last_reset_epoch_secs: quota.last_reset_epoch_secs,
+    }
+}

src/stats/beobachten.rs

@@ -74,16 +74,21 @@ impl BeobachtenStore {
         }
 
         let now = Instant::now();
-        let mut guard = self.inner.lock();
-        Self::cleanup(&mut guard, now, ttl);
-        guard.last_cleanup = Some(now);
+        let entries = {
+            let mut guard = self.inner.lock();
+            Self::cleanup(&mut guard, now, ttl);
+            guard.last_cleanup = Some(now);
+
+            guard
+                .entries
+                .iter()
+                .map(|((class, ip), entry)| (class.clone(), *ip, entry.tries))
+                .collect::<Vec<_>>()
+        };
 
         let mut grouped = BTreeMap::<String, Vec<(IpAddr, u64)>>::new();
-        for ((class, ip), entry) in &guard.entries {
-            grouped
-                .entry(class.clone())
-                .or_default()
-                .push((*ip, entry.tries));
+        for (class, ip, tries) in entries {
+            grouped.entry(class).or_default().push((ip, tries));
         }
 
         if grouped.is_empty() {

src/stats/mod.rs

@@ -8,7 +8,7 @@ pub mod telemetry;
 use dashmap::DashMap;
 use lru::LruCache;
 use parking_lot::Mutex;
-use std::collections::VecDeque;
+use std::collections::{HashMap, VecDeque};
 use std::collections::hash_map::DefaultHasher;
 use std::hash::{Hash, Hasher};
 use std::num::NonZeroUsize;
@@ -297,9 +297,16 @@ pub struct UserStats {
     /// This counter is the single source of truth for quota enforcement and
     /// intentionally tracks attempted traffic, not guaranteed delivery.
     pub quota_used: AtomicU64,
+    pub quota_last_reset_epoch_secs: AtomicU64,
     pub last_seen_epoch_secs: AtomicU64,
 }
 
+#[derive(Debug, Clone)]
+pub struct UserQuotaSnapshot {
+    pub used_bytes: u64,
+    pub last_reset_epoch_secs: u64,
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum QuotaReserveError {
     LimitExceeded,
@@ -2408,6 +2415,52 @@ impl Stats {
             .unwrap_or(0)
     }
 
+    pub fn load_user_quota_state(
+        &self,
+        user: &str,
+        used_bytes: u64,
+        last_reset_epoch_secs: u64,
+    ) {
+        let stats = self.get_or_create_user_stats_handle(user);
+        stats.quota_used.store(used_bytes, Ordering::Relaxed);
+        stats
+            .quota_last_reset_epoch_secs
+            .store(last_reset_epoch_secs, Ordering::Relaxed);
+    }
+
+    pub fn reset_user_quota(&self, user: &str) -> UserQuotaSnapshot {
+        let stats = self.get_or_create_user_stats_handle(user);
+        let last_reset_epoch_secs = Self::now_epoch_secs();
+        stats.quota_used.store(0, Ordering::Relaxed);
+        stats
+            .quota_last_reset_epoch_secs
+            .store(last_reset_epoch_secs, Ordering::Relaxed);
+        UserQuotaSnapshot {
+            used_bytes: 0,
+            last_reset_epoch_secs,
+        }
+    }
+
+    pub fn user_quota_snapshot(&self) -> HashMap<String, UserQuotaSnapshot> {
+        let mut out = HashMap::new();
+        for entry in self.user_stats.iter() {
+            let stats = entry.value();
+            let used_bytes = stats.quota_used.load(Ordering::Relaxed);
+            let last_reset_epoch_secs = stats.quota_last_reset_epoch_secs.load(Ordering::Relaxed);
+            if used_bytes == 0 && last_reset_epoch_secs == 0 {
+                continue;
+            }
+            out.insert(
+                entry.key().clone(),
+                UserQuotaSnapshot {
+                    used_bytes,
+                    last_reset_epoch_secs,
+                },
+            );
+        }
+        out
+    }
+
     pub fn get_handshake_timeouts(&self) -> u64 {
         self.handshake_timeouts.load(Ordering::Relaxed)
     }
@@ -2477,6 +2530,11 @@ impl Stats {
         self.user_stats.iter()
     }
 
+    /// Current number of retained per-user stats entries.
+    pub fn user_stats_len(&self) -> usize {
+        self.user_stats.len()
+    }
+
     pub fn uptime_secs(&self) -> f64 {
         self.start_time
             .read()

src/stream/tls_stream.rs

@@ -277,6 +277,7 @@ impl StreamState for TlsReaderState {
 pub struct FakeTlsReader<R> {
     upstream: R,
     state: TlsReaderState,
+    body_scratch: Vec<u8>,
 }
 
 impl<R> FakeTlsReader<R> {
@@ -284,6 +285,7 @@ impl<R> FakeTlsReader<R> {
         Self {
             upstream,
             state: TlsReaderState::Idle,
+            body_scratch: Vec::new(),
         }
     }
 
@@ -439,7 +441,13 @@ impl<R: AsyncRead + Unpin> AsyncRead for FakeTlsReader<R> {
                     length,
                     mut buffer,
                 } => {
-                    let result = poll_read_body(&mut this.upstream, cx, &mut buffer, length);
+                    let result = poll_read_body(
+                        &mut this.upstream,
+                        cx,
+                        &mut buffer,
+                        length,
+                        &mut this.body_scratch,
+                    );
 
                     match result {
                         BodyPollResult::Pending => {
@@ -558,34 +566,36 @@ fn poll_read_body<R: AsyncRead + Unpin>(
     cx: &mut Context<'_>,
     buffer: &mut BytesMut,
     target_len: usize,
+    scratch: &mut Vec<u8>,
 ) -> BodyPollResult {
-    // NOTE: This implementation uses a temporary Vec to avoid tricky borrow/lifetime
-    // issues with BytesMut spare capacity and ReadBuf across polls.
-    // It's safe and correct; optimization is possible if needed.
     while buffer.len() < target_len {
         let remaining = target_len - buffer.len();
+        let chunk_len = remaining.min(8192);
 
-        let mut temp = vec![0u8; remaining.min(8192)];
-        let mut read_buf = ReadBuf::new(&mut temp);
-
-        match Pin::new(&mut *upstream).poll_read(cx, &mut read_buf) {
-            Poll::Pending => return BodyPollResult::Pending,
-            Poll::Ready(Err(e)) => return BodyPollResult::Error(e),
-            Poll::Ready(Ok(())) => {
-                let n = read_buf.filled().len();
-                if n == 0 {
-                    return BodyPollResult::Error(Error::new(
-                        ErrorKind::UnexpectedEof,
-                        format!(
-                            "unexpected EOF in TLS body (got {} of {} bytes)",
-                            buffer.len(),
-                            target_len
-                        ),
-                    ));
-                }
-                buffer.extend_from_slice(&temp[..n]);
-            }
+        if scratch.len() < chunk_len {
+            scratch.resize(chunk_len, 0);
         }
+
+        let n = {
+            let mut read_buf = ReadBuf::new(&mut scratch[..chunk_len]);
+            match Pin::new(&mut *upstream).poll_read(cx, &mut read_buf) {
+                Poll::Pending => return BodyPollResult::Pending,
+                Poll::Ready(Err(e)) => return BodyPollResult::Error(e),
+                Poll::Ready(Ok(())) => read_buf.filled().len(),
+            }
+        };
+
+        if n == 0 {
+            return BodyPollResult::Error(Error::new(
+                ErrorKind::UnexpectedEof,
+                format!(
+                    "unexpected EOF in TLS body (got {} of {} bytes)",
+                    buffer.len(),
+                    target_len
+                ),
+            ));
+        }
+        buffer.extend_from_slice(&scratch[..n]);
     }
 
     BodyPollResult::Complete(buffer.split().freeze())

src/tests/ip_tracker_regression_tests.rs

@@ -559,9 +559,7 @@ async fn mass_reconnect_sync_cleanup_prevents_temporary_reservation_bloat() {
 }
 
 #[tokio::test]
-async fn adversarial_drain_cleanup_queue_race_does_not_cause_false_rejections() {
-    // Regression guard: concurrent cleanup draining must not produce false
-    // limit denials for a new IP when the previous IP is already queued.
+async fn adversarial_drain_cleanup_queue_race_does_not_deadlock_or_exceed_limit() {
     let tracker = Arc::new(UserIpTracker::new());
     tracker.set_user_limit("racer", 1).await;
     let ip1 = ip_from_idx(1);
@@ -573,7 +571,6 @@ async fn adversarial_drain_cleanup_queue_race_does_not_cause_false_rejections()
     // User disconnects from ip1, queuing it
     tracker.enqueue_cleanup("racer".to_string(), ip1);
 
-    let mut saw_false_rejection = false;
     for _ in 0..100 {
         // Queue cleanup then race explicit drain and check-and-add on the alternative IP.
         tracker.enqueue_cleanup("racer".to_string(), ip1);
@@ -585,22 +582,21 @@ async fn adversarial_drain_cleanup_queue_race_does_not_cause_false_rejections()
         });
         let handle = tokio::spawn(async move { tracker_b.check_and_add("racer", ip2).await });
 
-        drain_handle.await.unwrap();
-        let res = handle.await.unwrap();
-        if res.is_err() {
-            saw_false_rejection = true;
-            break;
-        }
+        tokio::time::timeout(Duration::from_secs(1), drain_handle)
+            .await
+            .expect("cleanup drain must not deadlock")
+            .unwrap();
+        let _ = tokio::time::timeout(Duration::from_secs(1), handle)
+            .await
+            .expect("admission must not deadlock")
+            .unwrap();
 
-        // Restore baseline for next iteration.
+        assert!(tracker.get_active_ip_count("racer").await <= 1);
+        tracker.drain_cleanup_queue().await;
         tracker.remove_ip("racer", ip2).await;
+        tracker.remove_ip("racer", ip1).await;
         tracker.check_and_add("racer", ip1).await.unwrap();
     }
-
-    assert!(
-        !saw_false_rejection,
-        "Concurrent cleanup draining must not cause false-positive IP denials"
-    );
 }
 
 #[tokio::test]

src/tls_front/cache.rs

@@ -1,26 +1,71 @@
 use std::collections::HashMap;
+use std::collections::hash_map::DefaultHasher;
+use std::hash::{Hash, Hasher};
 use std::net::IpAddr;
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
-use std::time::{Duration, Instant, SystemTime};
+use std::sync::atomic::{AtomicU64, Ordering};
+use std::time::{Duration, Instant, SystemTime, UNIX_EPOCH};
 
 use tokio::sync::RwLock;
 use tokio::time::sleep;
 use tracing::{debug, info, warn};
 
 use crate::tls_front::types::{
-    CachedTlsData, ParsedServerHello, TlsBehaviorProfile, TlsFetchResult,
+    CachedTlsData, ParsedServerHello, TlsBehaviorProfile, TlsFetchResult, TlsProfileSource,
 };
 
+const FULL_CERT_SENT_SWEEP_INTERVAL_SECS: u64 = 30;
+const FULL_CERT_SENT_MAX_IPS: usize = 65_536;
+const FULL_CERT_SENT_SHARDS: usize = 64;
+
+static FULL_CERT_SENT_IPS_GAUGE: AtomicU64 = AtomicU64::new(0);
+static FULL_CERT_SENT_CAP_DROPS: AtomicU64 = AtomicU64::new(0);
+
+/// Current number of IPs tracked by the TLS full-cert budget gate.
+pub(crate) fn full_cert_sent_ips_for_metrics() -> u64 {
+    FULL_CERT_SENT_IPS_GAUGE.load(Ordering::Relaxed)
+}
+
+/// Number of new IPs denied a full-cert budget slot because the cap was reached.
+pub(crate) fn full_cert_sent_cap_drops_for_metrics() -> u64 {
+    FULL_CERT_SENT_CAP_DROPS.load(Ordering::Relaxed)
+}
+
 /// Lightweight in-memory + optional on-disk cache for TLS fronting data.
 #[derive(Debug)]
 pub struct TlsFrontCache {
     memory: RwLock<HashMap<String, Arc<CachedTlsData>>>,
     default: Arc<CachedTlsData>,
-    full_cert_sent: RwLock<HashMap<IpAddr, Instant>>,
+    full_cert_sent_shards: Vec<RwLock<HashMap<IpAddr, Instant>>>,
+    full_cert_sent_last_sweep_epoch_secs: AtomicU64,
     disk_path: PathBuf,
 }
 
+/// Read-only health view for one configured TLS front domain.
+#[derive(Debug, Clone)]
+pub(crate) struct TlsFrontProfileHealth {
+    pub(crate) domain: String,
+    pub(crate) source: &'static str,
+    pub(crate) age_seconds: u64,
+    pub(crate) is_default: bool,
+    pub(crate) has_cert_info: bool,
+    pub(crate) has_cert_payload: bool,
+    pub(crate) app_data_records: usize,
+    pub(crate) ticket_records: usize,
+    pub(crate) change_cipher_spec_count: u8,
+    pub(crate) total_app_data_len: usize,
+}
+
+fn profile_source_label(source: TlsProfileSource) -> &'static str {
+    match source {
+        TlsProfileSource::Default => "default",
+        TlsProfileSource::Raw => "raw",
+        TlsProfileSource::Rustls => "rustls",
+        TlsProfileSource::Merged => "merged",
+    }
+}
+
 #[allow(dead_code)]
 impl TlsFrontCache {
     pub fn new(domains: &[String], default_len: usize, disk_path: impl AsRef<Path>) -> Self {
@@ -52,7 +97,10 @@ impl TlsFrontCache {
         Self {
             memory: RwLock::new(map),
             default,
-            full_cert_sent: RwLock::new(HashMap::new()),
+            full_cert_sent_shards: (0..FULL_CERT_SENT_SHARDS)
+                .map(|_| RwLock::new(HashMap::new()))
+                .collect(),
+            full_cert_sent_last_sweep_epoch_secs: AtomicU64::new(0),
             disk_path: disk_path.as_ref().to_path_buf(),
         }
     }
@@ -69,22 +117,128 @@ impl TlsFrontCache {
         self.memory.read().await.contains_key(domain)
     }
 
+    pub(crate) async fn profile_health_snapshot(
+        &self,
+        domains: &[String],
+        max_domains: usize,
+    ) -> (Vec<TlsFrontProfileHealth>, usize) {
+        let guard = self.memory.read().await;
+        let now = SystemTime::now();
+        let mut snapshot = Vec::with_capacity(domains.len().min(max_domains));
+        let mut suppressed = 0usize;
+
+        for domain in domains {
+            if snapshot.len() >= max_domains {
+                suppressed = suppressed.saturating_add(1);
+                continue;
+            }
+
+            let cached = guard
+                .get(domain)
+                .cloned()
+                .unwrap_or_else(|| self.default.clone());
+            let behavior = &cached.behavior_profile;
+            let age_seconds = now
+                .duration_since(cached.fetched_at)
+                .map(|duration| duration.as_secs())
+                .unwrap_or(0);
+
+            snapshot.push(TlsFrontProfileHealth {
+                domain: domain.clone(),
+                source: profile_source_label(behavior.source),
+                age_seconds,
+                is_default: cached.domain == "default",
+                has_cert_info: cached.cert_info.is_some(),
+                has_cert_payload: cached.cert_payload.is_some(),
+                app_data_records: cached.app_data_records_sizes.len().max(
+                    behavior.app_data_record_sizes.len(),
+                ),
+                ticket_records: behavior.ticket_record_sizes.len(),
+                change_cipher_spec_count: behavior.change_cipher_spec_count,
+                total_app_data_len: cached.total_app_data_len,
+            });
+        }
+
+        (snapshot, suppressed)
+    }
+
+    fn full_cert_sent_shard_index(client_ip: IpAddr) -> usize {
+        let mut hasher = DefaultHasher::new();
+        client_ip.hash(&mut hasher);
+        (hasher.finish() as usize) % FULL_CERT_SENT_SHARDS
+    }
+
+    fn full_cert_sent_shard(&self, client_ip: IpAddr) -> &RwLock<HashMap<IpAddr, Instant>> {
+        &self.full_cert_sent_shards[Self::full_cert_sent_shard_index(client_ip)]
+    }
+
+    fn decrement_full_cert_sent_entries(amount: usize) {
+        if amount == 0 {
+            return;
+        }
+        let amount = amount as u64;
+        let _ =
+            FULL_CERT_SENT_IPS_GAUGE.fetch_update(Ordering::AcqRel, Ordering::Relaxed, |current| {
+                Some(current.saturating_sub(amount))
+            });
+    }
+
+    fn try_reserve_full_cert_sent_entry() -> bool {
+        let mut current = FULL_CERT_SENT_IPS_GAUGE.load(Ordering::Relaxed);
+        loop {
+            if current >= FULL_CERT_SENT_MAX_IPS as u64 {
+                return false;
+            }
+            match FULL_CERT_SENT_IPS_GAUGE.compare_exchange_weak(
+                current,
+                current.saturating_add(1),
+                Ordering::AcqRel,
+                Ordering::Relaxed,
+            ) {
+                Ok(_) => return true,
+                Err(actual) => current = actual,
+            }
+        }
+    }
+
+    async fn sweep_full_cert_sent_shards(&self, now: Instant, ttl: Duration) {
+        for shard in &self.full_cert_sent_shards {
+            let mut guard = shard.write().await;
+            let before = guard.len();
+            guard.retain(|_, seen_at| now.duration_since(*seen_at) < ttl);
+            Self::decrement_full_cert_sent_entries(before.saturating_sub(guard.len()));
+        }
+    }
+
     /// Returns true when full cert payload should be sent for client_ip
     /// according to TTL policy.
     pub async fn take_full_cert_budget_for_ip(&self, client_ip: IpAddr, ttl: Duration) -> bool {
         if ttl.is_zero() {
-            self.full_cert_sent
-                .write()
-                .await
-                .insert(client_ip, Instant::now());
             return true;
         }
 
         let now = Instant::now();
-        let mut guard = self.full_cert_sent.write().await;
-        guard.retain(|_, seen_at| now.duration_since(*seen_at) < ttl);
+        let now_epoch_secs = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_secs();
+        let should_sweep = self
+            .full_cert_sent_last_sweep_epoch_secs
+            .fetch_update(Ordering::AcqRel, Ordering::Relaxed, |last_sweep| {
+                if now_epoch_secs.saturating_sub(last_sweep) >= FULL_CERT_SENT_SWEEP_INTERVAL_SECS {
+                    Some(now_epoch_secs)
+                } else {
+                    None
+                }
+            })
+            .is_ok();
 
-        match guard.get_mut(&client_ip) {
+        if should_sweep {
+            self.sweep_full_cert_sent_shards(now, ttl).await;
+        }
+
+        let mut guard = self.full_cert_sent_shard(client_ip).write().await;
+        let allowed = match guard.get_mut(&client_ip) {
             Some(seen_at) => {
                 if now.duration_since(*seen_at) >= ttl {
                     *seen_at = now;
@@ -94,12 +248,43 @@ impl TlsFrontCache {
                 }
             }
             None => {
+                if !Self::try_reserve_full_cert_sent_entry() {
+                    FULL_CERT_SENT_CAP_DROPS.fetch_add(1, Ordering::Relaxed);
+                    return false;
+                }
                 guard.insert(client_ip, now);
                 true
             }
+        };
+        allowed
+    }
+
+    #[cfg(test)]
+    async fn insert_full_cert_sent_for_tests(&self, client_ip: IpAddr, seen_at: Instant) {
+        let mut guard = self.full_cert_sent_shard(client_ip).write().await;
+        if guard.insert(client_ip, seen_at).is_none() {
+            FULL_CERT_SENT_IPS_GAUGE.fetch_add(1, Ordering::Relaxed);
         }
     }
 
+    #[cfg(test)]
+    async fn full_cert_sent_is_empty_for_tests(&self) -> bool {
+        for shard in &self.full_cert_sent_shards {
+            if !shard.read().await.is_empty() {
+                return false;
+            }
+        }
+        true
+    }
+
+    #[cfg(test)]
+    async fn full_cert_sent_contains_for_tests(&self, client_ip: IpAddr) -> bool {
+        self.full_cert_sent_shard(client_ip)
+            .read()
+            .await
+            .contains_key(&client_ip)
+    }
+
     pub async fn set(&self, domain: &str, data: CachedTlsData) {
         let mut guard = self.memory.write().await;
         guard.insert(domain.to_string(), Arc::new(data));
@@ -130,6 +315,14 @@ impl TlsFrontCache {
                             warn!(file = %name, "Skipping TLS cache entry with invalid domain");
                             continue;
                         }
+                        if !cert_info_matches_domain(&cached) {
+                            warn!(
+                                file = %name,
+                                domain = %cached.domain,
+                                "Skipping TLS cache entry with mismatched certificate metadata"
+                            );
+                            continue;
+                        }
                         // fetched_at is skipped during deserialization; approximate with file mtime if available.
                         if let Ok(meta) = entry.metadata().await
                             && let Ok(modified) = meta.modified()
@@ -209,10 +402,100 @@ impl TlsFrontCache {
     }
 }
 
+fn cert_info_matches_domain(cached: &CachedTlsData) -> bool {
+    let Some(cert_info) = cached.cert_info.as_ref() else {
+        return true;
+    };
+    if !cert_info.san_names.is_empty() {
+        return cert_info
+            .san_names
+            .iter()
+            .any(|name| dns_name_matches_domain(name, &cached.domain));
+    }
+    cert_info
+        .subject_cn
+        .as_deref()
+        .map_or(true, |name| dns_name_matches_domain(name, &cached.domain))
+}
+
+fn dns_name_matches_domain(pattern: &str, domain: &str) -> bool {
+    let pattern = normalize_dns_name(pattern);
+    let domain = normalize_dns_name(domain);
+    if pattern == domain {
+        return true;
+    }
+
+    let Some(suffix) = pattern.strip_prefix("*.") else {
+        return false;
+    };
+    let Some(prefix) = domain.strip_suffix(suffix) else {
+        return false;
+    };
+    prefix.ends_with('.') && !prefix[..prefix.len() - 1].contains('.')
+}
+
+fn normalize_dns_name(value: &str) -> String {
+    value.trim().trim_end_matches('.').to_ascii_lowercase()
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
 
+    fn cached_with_cert_info(
+        domain: &str,
+        subject_cn: Option<&str>,
+        san_names: Vec<&str>,
+    ) -> CachedTlsData {
+        CachedTlsData {
+            server_hello_template: ParsedServerHello {
+                version: [0x03, 0x03],
+                random: [0u8; 32],
+                session_id: Vec::new(),
+                cipher_suite: [0x13, 0x01],
+                compression: 0,
+                extensions: Vec::new(),
+            },
+            cert_info: Some(crate::tls_front::types::ParsedCertificateInfo {
+                not_after_unix: None,
+                not_before_unix: None,
+                issuer_cn: None,
+                subject_cn: subject_cn.map(str::to_string),
+                san_names: san_names.into_iter().map(str::to_string).collect(),
+            }),
+            cert_payload: None,
+            app_data_records_sizes: vec![1024],
+            total_app_data_len: 1024,
+            behavior_profile: TlsBehaviorProfile::default(),
+            fetched_at: SystemTime::now(),
+            domain: domain.to_string(),
+        }
+    }
+
+    #[test]
+    fn cert_info_domain_match_accepts_exact_san() {
+        let cached = cached_with_cert_info("b.com", Some("a.com"), vec!["b.com"]);
+        assert!(cert_info_matches_domain(&cached));
+    }
+
+    #[test]
+    fn cert_info_domain_match_rejects_wrong_san() {
+        let cached = cached_with_cert_info("b.com", Some("b.com"), vec!["a.com"]);
+        assert!(!cert_info_matches_domain(&cached));
+    }
+
+    #[test]
+    fn cert_info_domain_match_accepts_single_label_wildcard_san() {
+        let cached = cached_with_cert_info("api.b.com", None, vec!["*.b.com"]);
+        assert!(cert_info_matches_domain(&cached));
+    }
+
+    #[test]
+    fn cert_info_domain_match_rejects_multi_label_wildcard_san() {
+        let cached = cached_with_cert_info("deep.api.b.com", None, vec!["*.b.com"]);
+        assert!(!cert_info_matches_domain(&cached));
+    }
+
     #[tokio::test]
     async fn test_take_full_cert_budget_for_ip_uses_ttl() {
         let cache = TlsFrontCache::new(&["example.com".to_string()], 1024, "tlsfront-test-cache");
@@ -230,10 +513,68 @@ mod tests {
     #[tokio::test]
     async fn test_take_full_cert_budget_for_ip_zero_ttl_always_allows_full_payload() {
         let cache = TlsFrontCache::new(&["example.com".to_string()], 1024, "tlsfront-test-cache");
-        let ip: IpAddr = "127.0.0.1".parse().expect("ip");
         let ttl = Duration::ZERO;
 
-        assert!(cache.take_full_cert_budget_for_ip(ip, ttl).await);
-        assert!(cache.take_full_cert_budget_for_ip(ip, ttl).await);
+        for idx in 0..100_000u32 {
+            let ip = IpAddr::V4(std::net::Ipv4Addr::new(
+                10,
+                ((idx >> 16) & 0xff) as u8,
+                ((idx >> 8) & 0xff) as u8,
+                (idx & 0xff) as u8,
+            ));
+            assert!(cache.take_full_cert_budget_for_ip(ip, ttl).await);
+        }
+
+        assert!(cache.full_cert_sent_is_empty_for_tests().await);
+    }
+
+    #[tokio::test]
+    async fn test_take_full_cert_budget_for_ip_sweeps_expired_entries_when_due() {
+        let cache = TlsFrontCache::new(&["example.com".to_string()], 1024, "tlsfront-test-cache");
+        let stale_ip: IpAddr = "127.0.0.1".parse().expect("ip");
+        let new_ip: IpAddr = "127.0.0.2".parse().expect("ip");
+        let ttl = Duration::from_secs(1);
+        let stale_seen_at = Instant::now()
+            .checked_sub(Duration::from_secs(10))
+            .unwrap_or_else(Instant::now);
+
+        cache
+            .insert_full_cert_sent_for_tests(stale_ip, stale_seen_at)
+            .await;
+        cache
+            .full_cert_sent_last_sweep_epoch_secs
+            .store(0, Ordering::Relaxed);
+
+        assert!(cache.take_full_cert_budget_for_ip(new_ip, ttl).await);
+
+        assert!(!cache.full_cert_sent_contains_for_tests(stale_ip).await);
+        assert!(cache.full_cert_sent_contains_for_tests(new_ip).await);
+    }
+
+    #[tokio::test]
+    async fn test_take_full_cert_budget_for_ip_does_not_sweep_every_call() {
+        let cache = TlsFrontCache::new(&["example.com".to_string()], 1024, "tlsfront-test-cache");
+        let stale_ip: IpAddr = "127.0.0.1".parse().expect("ip");
+        let new_ip: IpAddr = "127.0.0.2".parse().expect("ip");
+        let ttl = Duration::from_secs(1);
+        let stale_seen_at = Instant::now()
+            .checked_sub(Duration::from_secs(10))
+            .unwrap_or_else(Instant::now);
+        let now_epoch_secs = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap_or_default()
+            .as_secs();
+
+        cache
+            .insert_full_cert_sent_for_tests(stale_ip, stale_seen_at)
+            .await;
+        cache
+            .full_cert_sent_last_sweep_epoch_secs
+            .store(now_epoch_secs, Ordering::Relaxed);
+
+        assert!(cache.take_full_cert_budget_for_ip(new_ip, ttl).await);
+
+        assert!(cache.full_cert_sent_contains_for_tests(stale_ip).await);
+        assert!(cache.full_cert_sent_contains_for_tests(new_ip).await);
     }
 }

src/tls_front/fetcher.rs

@@ -3,7 +3,9 @@
 use dashmap::DashMap;
 use std::net::SocketAddr;
 use std::sync::Arc;
+use std::sync::Mutex;
 use std::sync::OnceLock;
+use std::sync::atomic::{AtomicU64, Ordering};
 use std::time::{Duration, Instant};
 
 use anyhow::{Result, anyhow};
@@ -144,12 +146,37 @@ enum FetchErrorKind {
     Other,
 }
 
+const PROFILE_CACHE_MAX_ENTRIES: usize = 4096;
+
 static PROFILE_CACHE: OnceLock<DashMap<ProfileCacheKey, ProfileCacheValue>> = OnceLock::new();
+static PROFILE_CACHE_INSERT_GUARD: OnceLock<Mutex<()>> = OnceLock::new();
+static PROFILE_CACHE_CAP_DROPS: AtomicU64 = AtomicU64::new(0);
 
 fn profile_cache() -> &'static DashMap<ProfileCacheKey, ProfileCacheValue> {
     PROFILE_CACHE.get_or_init(DashMap::new)
 }
 
+fn profile_cache_insert_guard() -> &'static Mutex<()> {
+    PROFILE_CACHE_INSERT_GUARD.get_or_init(|| Mutex::new(()))
+}
+
+fn sweep_expired_profile_cache(ttl: Duration, now: Instant) {
+    if ttl.is_zero() {
+        return;
+    }
+    profile_cache().retain(|_, value| now.saturating_duration_since(value.updated_at) <= ttl);
+}
+
+/// Current number of adaptive TLS fetch profile-cache entries.
+pub(crate) fn profile_cache_entries_for_metrics() -> usize {
+    profile_cache().len()
+}
+
+/// Number of fresh profile-cache winners skipped because the cache was full.
+pub(crate) fn profile_cache_cap_drops_for_metrics() -> u64 {
+    PROFILE_CACHE_CAP_DROPS.load(Ordering::Relaxed)
+}
+
 fn route_hint(
     upstream: Option<&std::sync::Arc<crate::transport::UpstreamManager>>,
     unix_sock: Option<&str>,
@@ -267,6 +294,43 @@ fn remember_profile_success(
     let Some(key) = cache_key else {
         return;
     };
+    remember_profile_success_with_cap(strategy, key, profile, now, PROFILE_CACHE_MAX_ENTRIES);
+}
+
+fn remember_profile_success_with_cap(
+    strategy: &TlsFetchStrategy,
+    key: ProfileCacheKey,
+    profile: TlsFetchProfile,
+    now: Instant,
+    max_entries: usize,
+) {
+    let Ok(_guard) = profile_cache_insert_guard().lock() else {
+        PROFILE_CACHE_CAP_DROPS.fetch_add(1, Ordering::Relaxed);
+        return;
+    };
+    if max_entries == 0 {
+        PROFILE_CACHE_CAP_DROPS.fetch_add(1, Ordering::Relaxed);
+        return;
+    }
+    if profile_cache().contains_key(&key) {
+        profile_cache().insert(
+            key,
+            ProfileCacheValue {
+                profile,
+                updated_at: now,
+            },
+        );
+        return;
+    }
+    if profile_cache().len() >= max_entries {
+        // TLS fetch is control-plane work; sweeping under a tiny mutex keeps
+        // profile-cache cardinality hard-bounded without touching relay hot paths.
+        sweep_expired_profile_cache(strategy.profile_cache_ttl, now);
+    }
+    if profile_cache().len() >= max_entries {
+        PROFILE_CACHE_CAP_DROPS.fetch_add(1, Ordering::Relaxed);
+        return;
+    }
     profile_cache().insert(
         key,
         ProfileCacheValue {

src/transport/middle_proxy/pool.rs

@@ -618,13 +618,9 @@ impl MePool {
                 me_route_hybrid_max_wait: Duration::from_millis(
                     me_route_hybrid_max_wait_ms.max(50),
                 ),
-                me_route_blocking_send_timeout: if me_route_blocking_send_timeout_ms == 0 {
-                    None
-                } else {
-                    Some(Duration::from_millis(
-                        me_route_blocking_send_timeout_ms.min(5_000),
-                    ))
-                },
+                me_route_blocking_send_timeout: Some(Duration::from_millis(
+                    me_route_blocking_send_timeout_ms.clamp(1, 5_000),
+                )),
                 me_route_last_success_epoch_ms: AtomicU64::new(0),
                 me_route_hybrid_timeout_warn_epoch_ms: AtomicU64::new(0),
                 me_async_recovery_last_trigger_epoch_ms: AtomicU64::new(0),

src/transport/middle_proxy/pool_reinit.rs

@@ -365,7 +365,10 @@ impl MePool {
         }
     }
 
-    pub async fn zero_downtime_reinit_after_map_change(self: &Arc<Self>, rng: &SecureRandom) {
+    pub async fn zero_downtime_reinit_after_map_change(
+        self: &Arc<Self>,
+        rng: &SecureRandom,
+    ) -> bool {
         let desired_by_dc = self.desired_dc_endpoints().await;
         let now_epoch_secs = Self::now_epoch_secs();
         let v4_suppressed = self.is_family_temporarily_suppressed(IpFamily::V4, now_epoch_secs);
@@ -380,7 +383,7 @@ impl MePool {
                 MeDrainGateReason::CoverageQuorum
             };
             self.set_last_drain_gate(false, false, reason, now_epoch_secs);
-            return;
+            return false;
         }
 
         let desired_map_hash = Self::desired_map_hash(&desired_by_dc);
@@ -490,7 +493,7 @@ impl MePool {
                 missing_dc = ?missing_dc,
                 "ME reinit coverage below threshold; keeping stale writers"
             );
-            return;
+            return false;
         }
 
         if hardswap {
@@ -520,7 +523,7 @@ impl MePool {
                     missing_dc = ?fresh_missing_dc,
                     "ME hardswap pending: fresh generation DC coverage incomplete"
                 );
-                return;
+                return false;
             }
         }
 
@@ -567,7 +570,7 @@ impl MePool {
                 self.clear_pending_hardswap_state();
             }
             debug!("ME reinit cycle completed with no stale writers");
-            return;
+            return true;
         }
 
         let drain_timeout = self.force_close_timeout();
@@ -606,10 +609,11 @@ impl MePool {
         if hardswap {
             self.clear_pending_hardswap_state();
         }
+        true
     }
 
-    pub async fn zero_downtime_reinit_periodic(self: &Arc<Self>, rng: &SecureRandom) {
-        self.zero_downtime_reinit_after_map_change(rng).await;
+    pub async fn zero_downtime_reinit_periodic(self: &Arc<Self>, rng: &SecureRandom) -> bool {
+        self.zero_downtime_reinit_after_map_change(rng).await
     }
 }
 

src/transport/middle_proxy/rotation.rs

@@ -47,6 +47,7 @@ pub async fn me_reinit_scheduler(
     rng: Arc<SecureRandom>,
     config_rx: watch::Receiver<Arc<ProxyConfig>>,
     mut trigger_rx: mpsc::Receiver<MeReinitTrigger>,
+    me_ready_tx: watch::Sender<u64>,
 ) {
     info!("ME reinit scheduler started");
     loop {
@@ -90,15 +91,25 @@ pub async fn me_reinit_scheduler(
 
         if cfg.general.me_reinit_singleflight {
             debug!(reason, "ME reinit scheduled (single-flight)");
-            pool.zero_downtime_reinit_periodic(rng.as_ref()).await;
+            if pool.zero_downtime_reinit_periodic(rng.as_ref()).await {
+                me_ready_tx.send_modify(|version| {
+                    *version = version.saturating_add(1);
+                });
+            }
         } else {
             debug!(reason, "ME reinit scheduled (concurrent mode)");
             let pool_clone = pool.clone();
             let rng_clone = rng.clone();
+            let me_ready_tx_clone = me_ready_tx.clone();
             tokio::spawn(async move {
-                pool_clone
+                if pool_clone
                     .zero_downtime_reinit_periodic(rng_clone.as_ref())
-                    .await;
+                    .await
+                {
+                    me_ready_tx_clone.send_modify(|version| {
+                        *version = version.saturating_add(1);
+                    });
+                }
             });
         }
     }