release: 1.4.1 — TCP fallback, Russian sites direct in the Android client

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-23 03:27:23 +03:00
parent 071d3695e6
commit dff6af2c8e
16 changed files with 361 additions and 23 deletions
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,13 @@ phobos-update beta      # или: phobos-update dev

 ---

+## 1.4.1 — резервный TCP-канал, «РФ напрямую»
+
+- **feat:** резервный канал TCP: если провайдер режет UDP, клиент сам переходит на TCP (порт 443, иначе 8443/2096/4433). Сервер: служба `phobos-tcp` (`udptcp`), ставится и включается автоматически при установке и обновлении. Проверено реальной блокировкой UDP: переключение за ~15 с, без блокировки остаётся UDP.
+- **feat (Android 1.4.2):** «Российские сайты — напрямую, без VPN» (по умолчанию), выбор канала Авто/UDP/TCP, журнал TCP-канала.
+- **fix:** установка и обновления с git.bobyrev.com (GitHub — запасной), каскад раздаёт панель.
+- Ограничения: TCP-резерв пока только на основном сервере (не на вторых) и только в приложении PCA Phobos VPN (роутеры и PhobosWG — по-прежнему UDP с перебором портов).
+
 ## 1.4.0 — единая версия (stable = beta = dev)

 Три канала сведены в одну версию: всё из dev (WARP, ttyd, бэкап, маршрут Keenetic, параметры обфускатора)
--- a/README.md
+++ b/README.md
@@ -38,6 +38,7 @@
 - **Замер скорости** — сервера (реальная скачка/отдача, кнопка ⚡ на «Серверах»), клиента (живая скорость в карточке + страница `http://10.25.0.1:<порт>/speedtest` на устройстве через VPN).
 - **Домен панели** — `https://ваш-домен/` с бесплатным сертификатом Let's Encrypt; старый адрес `http://IP:порт` продолжает работать.
 - **Адрес для клиентов и каскад** — клиенты подключаются по домену или через входной сервер (например, в РФ) → ваш сервер; роутеры получают адрес сами.
+- **Резервный TCP-канал** — если провайдер режет UDP, клиент сам переходит на TCP (порт 443), обфускация сохраняется.
 - **Сторож** — блокировка зондов и сканеров РКН (nftables, список обновляется раз в сутки).
 - **WARP / WARP+** — выпуск клиентов в интернет через Cloudflare WARP (всем или выборочно), relay-режим.
 - **Бэкап и восстановление** сервера из панели; **терминал роутера в браузере** (ttyd/RCI) за NAT.
@@ -136,8 +137,8 @@ bash <(curl -fsSL https://git.bobyrev.com/PCA/PCA_Phobos/raw/branch/main/server/

 ## Приложения для Android

- **PCA Phobos VPN** — клиент: включает VPN одной кнопкой, импорт `phobos://` из панели, встроенный обфускатор, **раздельный трафик** (весь / только выбранные приложения / все кроме выбранных), журнал, проверка скорости. [Скачать APK](https://git.bobyrev.com/PCA/PCA_Phobos/releases/download/v1.4.0/PCA-Phobos-VPN.apk) · исходники `android-client/`.
- **PCA Phobos** (админ) — список ваших панелей, открываются в приложении. [Скачать APK](https://git.bobyrev.com/PCA/PCA_Phobos/releases/download/v1.4.0/PCA-Phobos.apk) · исходники `android/`.
+- **PCA Phobos VPN** — клиент: включает VPN одной кнопкой, импорт `phobos://` из панели, встроенный обфускатор, **раздельный трафик** (весь / только выбранные приложения / все кроме выбранных), **российские сайты напрямую** (по умолчанию), **канал Авто/UDP/TCP** (при блокировке UDP — сам на TCP), журнал, проверка скорости. [Скачать APK](https://git.bobyrev.com/PCA/PCA_Phobos/releases/download/v1.4.1/PCA-Phobos-VPN.apk) · исходники `android-client/`.
+- **PCA Phobos** (админ) — список ваших панелей, открываются в приложении. [Скачать APK](https://git.bobyrev.com/PCA/PCA_Phobos/releases/download/v1.4.1/PCA-Phobos.apk) · исходники `android/`.

 ## Клиенты для телефона

--- a/2
+++ b/2
@@ -1 +1 @@
-1.4.0
+1.4.1
--- a/android-client/AndroidManifest.xml
+++ b/android-client/AndroidManifest.xml
@@ -1,8 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.pca.phobos.vpn"
-    android:versionCode="141"
-    android:versionName="1.4.1">
+    android:versionCode="142"
+    android:versionName="1.4.2">

    <uses-sdk android:minSdkVersion="24" android:targetSdkVersion="35" />
    <uses-permission android:name="android.permission.INTERNET" />
--- a/android-client/build.sh
+++ b/android-client/build.sh
@@ -17,7 +17,8 @@ LIBS="build/aar/classes.jar:$(ls libs/*.jar | tr '\n' ':')"
 "$BT/aapt2" link -o build/base.apk -I "$JAR" --manifest AndroidManifest.xml -A assets \
    --java build/gen build/res/*.flat --min-sdk-version 24 --target-sdk-version 35
 javac -source 11 -target 11 -nowarn -classpath "$JAR:$LIBS" -d build/classes \
-    $(find src build/gen -name '*.java') 2>&1 | grep -v "bootstrap classpath\|^Note:" || true
+    $(find src build/gen -name '*.java') 2>&1 | grep -v "bootstrap classpath\|^Note:\|^warning: \[options\]\|^1 warning" || true
+[ -f build/classes/com/pca/phobos/vpn/MainActivity.class ] || { echo "javac failed"; exit 1; }
 "$BT/d8" --release --lib "$JAR" --min-api 24 --output build/dex \
    $(find build/classes -name '*.class') build/aar/classes.jar libs/*.jar
 cp build/base.apk build/unsigned.apk
@@ -25,7 +26,7 @@ cp build/base.apk build/unsigned.apk
 for abi in arm64-v8a armeabi-v7a; do
    mkdir -p "build/apk/lib/$abi"
    cp build/aar/jni/$abi/*.so "build/apk/lib/$abi/"
-    cp "jni/$abi/libwgobfuscator.so" "build/apk/lib/$abi/"
+    cp "jni/$abi/libwgobfuscator.so" "jni/$abi/libudptcp.so" "build/apk/lib/$abi/"
 done
 (cd build/apk && zip -qr ../unsigned.apk lib)
 "$BT/zipalign" -f 4 build/unsigned.apk build/aligned.apk
--- a/android-client/jni/arm64-v8a/libudptcp.so
+++ b/android-client/jni/arm64-v8a/libudptcp.so
--- a/android-client/jni/armeabi-v7a/libudptcp.so
+++ b/android-client/jni/armeabi-v7a/libudptcp.so
--- a/android-client/src/com/pca/phobos/vpn/MainActivity.java
+++ b/android-client/src/com/pca/phobos/vpn/MainActivity.java
@@ -59,7 +59,9 @@ public class MainActivity extends Activity {
    static final String MODE_ALL = "all", MODE_ONLY = "only", MODE_EXCEPT = "except";

    static GoBackend backend;
-    static Process obfuscator;
+    static Process obfuscator, relay;
+    static final int TCP_LPORT = 13256;
+    static volatile String transport = "";      // "UDP" | "TCP" while up
    static final Tunnel TUNNEL = new Tunnel() {
        public String getName() { return "phobos"; }
        public void onStateChange(Tunnel.State s) { }
@@ -215,17 +217,27 @@ public class MainActivity extends Activity {

    private static String getPackageNameSafe() { return "com.pca.phobos.vpn"; }

-    private String obfPart(String conf) {
+    private String obfPart(String conf, boolean viaTcp) {
        StringBuilder sb = new StringBuilder("[instance]\nsource-if = 127.0.0.1\nsource-lport = " + LPORT + "\n");
        for (String ln : section(conf, "[instance]")) {
            String k = key(ln);
            if (k.equals("source-if") || k.equals("source-lport") || k.equals("verbose")) continue;
+            if (viaTcp && k.equals("target")) ln = "target = 127.0.0.1:" + TCP_LPORT;
            sb.append(ln).append('\n');
        }
        sb.append("verbose = INFO\n");
        return sb.toString();
    }

+    /** "# pca-tcp = 443" written by the panel when the server has the TCP fallback. */
+    private static String tcpPort(String conf) {
+        for (String ln : conf.split("\n")) {
+            String t = ln.trim();
+            if (t.startsWith("#") && t.contains("pca-tcp") && t.contains("=")) return val(t);
+        }
+        return "";
+    }
+
    private String target(String conf) {
        for (String ln : section(conf, "[instance]")) if (key(ln).equals("target")) return val(ln);
        return "?";
@@ -250,24 +262,39 @@ public class MainActivity extends Activity {
        else if (req == 7) toast("Без разрешения на VPN подключиться нельзя");
    }

+    /** Start (or restart) obfuscator; via TCP it dials the local udptcp relay. */
+    private void startTransport(String conf, boolean viaTcp) throws Exception {
+        stopObfuscator();
+        String lib = getApplicationInfo().nativeLibraryDir;
+        if (viaTcp) {
+            String host = target(conf).replaceAll(":\\d+$", "");
+            relay = new ProcessBuilder(lib + "/libudptcp.so", "-c", "127.0.0.1:" + TCP_LPORT, host + ":" + tcpPort(conf))
+                    .redirectErrorStream(true).redirectOutput(new File(getFilesDir(), "tcp.log")).start();
+        }
+        File cfg = new File(getFilesDir(), "obf.conf");
+        try (FileOutputStream o = new FileOutputStream(cfg)) { o.write(obfPart(conf, viaTcp).getBytes(StandardCharsets.UTF_8)); }
+        obfuscator = new ProcessBuilder(lib + "/libwgobfuscator.so", "-c", cfg.getAbsolutePath())
+                .redirectErrorStream(true).redirectOutput(new File(getFilesDir(), "obf.log")).start();
+        Thread.sleep(600);
+        if (!obfuscator.isAlive()) throw new IllegalStateException("обфускатор завершился, код " + obfuscator.exitValue() + " — см. «Журнал»");
+        if (relay != null && !relay.isAlive()) throw new IllegalStateException("TCP-канал не запустился — см. «Журнал»");
+        transport = viaTcp ? "TCP" : "UDP";
+        log("transport " + transport + " -> " + target(conf) + (viaTcp ? " tcp:" + tcpPort(conf) : ""));
+    }
+
    private void up() {
        try {
            String conf = prefs.getString("conf", "");
-            File cfg = new File(getFilesDir(), "obf.conf");
-            try (FileOutputStream o = new FileOutputStream(cfg)) { o.write(obfPart(conf).getBytes(StandardCharsets.UTF_8)); }
-            stopObfuscator();
-            String bin = getApplicationInfo().nativeLibraryDir + "/libwgobfuscator.so";
-            obfuscator = new ProcessBuilder(bin, "-c", cfg.getAbsolutePath())
-                    .redirectErrorStream(true)
-                    .redirectOutput(new File(getFilesDir(), "obf.log"))
-                    .start();
-            Thread.sleep(600);
-            if (!obfuscator.isAlive()) throw new IllegalStateException("обфускатор завершился, код " + obfuscator.exitValue() + " — см. «Журнал»");
+            String mode = prefs.getString("transport", "auto");
+            boolean tcpAvail = !tcpPort(conf).isEmpty();
+            if ("tcp".equals(mode) && !tcpAvail) throw new IllegalStateException("на сервере нет TCP-канала — обновите панель и заново импортируйте ссылку");
+            startTransport(conf, "tcp".equals(mode));
            Config c = Config.parse(new BufferedReader(new StringReader(
                    wgPart(conf, prefs.getString("mode", MODE_ALL), prefs.getString("apps", "")))));
            backend.setState(TUNNEL, Tunnel.State.UP, c);
-            log("up ok, target " + target(conf) + ", mode " + prefs.getString("mode", MODE_ALL));
-            post("Подключено");
+            log("up ok, mode " + prefs.getString("mode", MODE_ALL) + ", transport " + mode);
+            post("Подключено (" + transport + ")");
+            if ("auto".equals(mode) && tcpAvail) watchUdp(conf);
        } catch (Throwable e) {
            stopObfuscator();
            log("up failed: " + e);
@@ -275,14 +302,30 @@ public class MainActivity extends Activity {
        }
    }

+    /** Auto: no bytes back over UDP within 15 s -> UDP is cut, move the obfuscator to TCP. */
+    private void watchUdp(String conf) {
+        new Thread(() -> {
+            try {
+                Thread.sleep(15000);
+                if (!isUp() || !"UDP".equals(transport)) return;
+                if (backend.getStatistics(TUNNEL).totalRx() > 0) return;
+                log("UDP: no answer in 15 s -> switching to TCP");
+                startTransport(conf, true);
+                post("UDP не отвечает — переключился на TCP");
+            } catch (Throwable e) { log("watchUdp: " + e); }
+        }).start();
+    }
+
    private void down() {
        try { backend.setState(TUNNEL, Tunnel.State.DOWN, null); } catch (Throwable ignored) { }
        stopObfuscator();
+        transport = "";
        post("Отключено");
    }

    private static void stopObfuscator() {
        if (obfuscator != null) { obfuscator.destroy(); obfuscator = null; }
+        if (relay != null) { relay.destroy(); relay = null; }
    }

    private void post(String msg) { ui.post(() -> { toast(msg); refresh(); }); }
@@ -364,6 +407,20 @@ public class MainActivity extends Activity {
        ru.setChecked(prefs.getBoolean("ru_direct", true));
        ru.setOnCheckedChangeListener((b, on) -> { prefs.edit().putBoolean("ru_direct", on).apply(); applyIfUp(); });
        split.addView(ru, mw(4));
+        split.addView(tv("Канал до сервера", text(), 14, true), mw(8));
+        RadioGroup tg = new RadioGroup(this);
+        tg.setOrientation(RadioGroup.HORIZONTAL);
+        String tmode = prefs.getString("transport", "auto");
+        for (String[] m : new String[][]{{"auto", "Авто"}, {"udp", "UDP"}, {"tcp", "TCP"}}) {
+            RadioButton r = new RadioButton(this);
+            r.setText(m[1]);
+            r.setTextColor(text());
+            r.setId(View.generateViewId());
+            r.setChecked(m[0].equals(tmode));
+            r.setOnClickListener(v -> { prefs.edit().putString("transport", m[0]).apply(); applyIfUp(); });
+            tg.addView(r);
+        }
+        split.addView(tg);
        int n = prefs.getString("apps", "").isEmpty() ? 0 : prefs.getString("apps", "").split(",").length;
        split.addView(button("Выбрать приложения (" + n + ")", 0xFF475569, v -> pickApps()), mw(8));
        split.addView(tv("Изменения применяются сразу. Само приложение всегда идёт напрямую — так обфускатор держит связь с сервером.",
@@ -385,7 +442,7 @@ public class MainActivity extends Activity {
        boolean up = isUp();
        power.setText(up ? "Отключить" : "Подключить");
        power.setBackground(round(up ? 0xFF16A34A : 0xFF4F46E5, 90));
-        status.setText(up ? "🟢 VPN включён" : "⚪ VPN выключен");
+        status.setText(up ? "🟢 VPN включён" + (transport.isEmpty() ? "" : " · " + transport) : "⚪ VPN выключен");
        if (up) {
            try {
                Statistics st = backend.getStatistics(TUNNEL);
@@ -466,6 +523,7 @@ public class MainActivity extends Activity {
    private void showLog() {
        String t = "— приложение —\n" + tail(new File(getFilesDir(), "app.log"), 3000)
                + "\n— обфускатор —\n" + tail(new File(getFilesDir(), "obf.log"), 3000)
+                + "\n— TCP-канал —\n" + tail(new File(getFilesDir(), "tcp.log"), 1500)
                + "\nобфускатор запущен: " + (obfuscator != null && obfuscator.isAlive());
        TextView v = tv(t, text(), 12, false);
        v.setTextIsSelectable(true);
--- a/app.py
+++ b/app.py
@@ -37,7 +37,7 @@ WG_CONFIG = "/etc/wireguard/wg0.conf"
 # Distribution: Gitea first (GitHub account is unavailable since 23.10.2026), GitHub fallback
 PCA_GIT = "https://git.bobyrev.com/PCA/PCA_Phobos"
 PCA_GH_RAW = "https://raw.githubusercontent.com/andrey271192/PCA_Phobos"
-APK_TAG = "v1.4.0"
+APK_TAG = "v1.4.1"
 WARP_DIR = f"{PHOBOS_DIR}/server/warp"
 WARP_CUSTOM_PROFILE_FILE = f"{WARP_DIR}/custom-profile.conf"
 WARP_LICENSE_FILE = f"{WARP_DIR}/license.key"
@@ -1390,6 +1390,10 @@ def build_phone_config(cid, mode="android"):
            ("target = " + _swap_host(ln.split("=", 1)[1].strip(), client_endpoint))
            if ln.strip().startswith("target") and "=" in ln else ln
            for ln in inst.split("\n"))
+        tcp_port = _load_server_env().get("TCP_PORT", "")
+        if tcp_port and "pca-tcp" not in inst:
+            # comment: PhobosWG/wg-obfuscator ignore it, PCA Phobos VPN uses it for the TCP fallback
+            inst += "\n# pca-tcp = " + tcp_port
    conf = wg + "\n\n" + inst + "\n"
    payload = _prepare_phoboswg_payload(conf)
    b64 = base64.urlsafe_b64encode(payload.encode()).decode()
--- a/install.sh
+++ b/install.sh
@@ -243,6 +243,8 @@ fetch server/phobos-cascade.sh              "$PHOBOS_DIR/server/phobos-cascade.s
 fetch server/phobos-domain.sh               "$PHOBOS_DIR/server/phobos-domain.sh"             && chmod +x "$PHOBOS_DIR/server/phobos-domain.sh" && ln -sf "$PHOBOS_DIR/server/phobos-domain.sh" /usr/local/bin/phobos-domain
 fetch server/phobos-limit.sh                "$PHOBOS_DIR/server/phobos-limit.sh"              && chmod +x "$PHOBOS_DIR/server/phobos-limit.sh"
 fetch server/phobos-speedtest.sh            "$PHOBOS_DIR/server/phobos-speedtest.sh"          && chmod +x "$PHOBOS_DIR/server/phobos-speedtest.sh"
+fetch server/phobos-tcp.sh                  "$PHOBOS_DIR/server/phobos-tcp.sh"                && chmod +x "$PHOBOS_DIR/server/phobos-tcp.sh" && ln -sf "$PHOBOS_DIR/server/phobos-tcp.sh" /usr/local/bin/phobos-tcp
+fetch "udptcp/bin/udptcp-$OBF_ARCH"         "$PHOBOS_DIR/bin/udptcp"                          && chmod +x "$PHOBOS_DIR/bin/udptcp"
 fetch server/phobos-health.sh                   "$PHOBOS_DIR/server/phobos-health.sh"                     && chmod +x "$PHOBOS_DIR/server/phobos-health.sh"
 fetch server/phobos-self-check.sh               "$PHOBOS_DIR/server/phobos-self-check.sh"                 && chmod +x "$PHOBOS_DIR/server/phobos-self-check.sh" && ln -sf "$PHOBOS_DIR/server/phobos-self-check.sh" /usr/local/bin/phobos-self-check
 fetch server/phobos-pull.sh                     "$PHOBOS_DIR/server/phobos-pull.sh"                       && chmod +x "$PHOBOS_DIR/server/phobos-pull.sh"
@@ -298,6 +300,9 @@ WantedBy=multi-user.target
 EOF
 systemctl daemon-reload; systemctl enable phobos-panel -q; systemctl restart phobos-panel

+# TCP fallback for clients whose UDP is cut (port 443/8443/... picked automatically)
+"$PHOBOS_DIR/server/phobos-tcp.sh" enable || echo "  WARN: TCP fallback not enabled"
+
 # ── 8. nginx (serve /init + /packages over plain HTTP for routers) ──
 echo "[8/9] nginx..."
 rm -f /etc/nginx/sites-enabled/default 2>/dev/null || true
--- a/server/phobos-tcp.sh
+++ b/server/phobos-tcp.sh
@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+# PCA Phobos — TCP fallback: clients whose UDP is cut reach the obfuscator over TCP.
+# udptcp -s 0.0.0.0:<TCP_PORT> -> 127.0.0.1:<first obfuscator port> (UDP).
+#   phobos-tcp.sh enable [port]   pick a free port (443, 8443, 2096) unless given; idempotent
+#   phobos-tcp.sh disable | status
+set -uo pipefail
+PHOBOS_DIR=/opt/Phobos
+ENV="$PHOBOS_DIR/server/server.env"
+BIN="$PHOBOS_DIR/bin/udptcp"
+
+env_get() { grep -E "^$1=" "$ENV" 2>/dev/null | tail -1 | cut -d= -f2-; }
+env_set() {
+    grep -v -E "^$1=" "$ENV" > "$ENV.tmp" 2>/dev/null || true
+    echo "$1=$2" >> "$ENV.tmp" && mv "$ENV.tmp" "$ENV"
+}
+port_busy() { ss -lntH "sport = :$1" 2>/dev/null | grep -q .; }
+
+enable() {
+    [ -x "$BIN" ] || { echo "udptcp binary missing: $BIN (phobos-update)" >&2; exit 1; }
+    local port="${1:-$(env_get TCP_PORT)}" obf
+    obf=$(env_get OBFUSCATOR_PORTS | cut -d, -f1); obf="${obf:-2083}"
+    # keep our own port if the service already holds it
+    if [ -z "$port" ] || { port_busy "$port" && ! systemctl is-active -q phobos-tcp; }; then
+        port=""
+        for p in 443 8443 2096 4433; do port_busy "$p" || { port=$p; break; }; done
+    fi
+    [ -n "$port" ] || { echo "no free TCP port (443/8443/2096/4433)" >&2; exit 1; }
+    env_set TCP_PORT "$port"
+    cat > /etc/systemd/system/phobos-tcp.service <<EOF
+[Unit]
+Description=PCA Phobos TCP fallback (udptcp -> obfuscator :$obf)
+After=network-online.target
+Wants=network-online.target
+[Service]
+ExecStart=$BIN -s 0.0.0.0:$port 127.0.0.1:$obf
+Restart=always
+RestartSec=3
+[Install]
+WantedBy=multi-user.target
+EOF
+    systemctl daemon-reload
+    systemctl enable -q phobos-tcp
+    systemctl restart phobos-tcp
+    sleep 1
+    status
+}
+
+disable() {
+    systemctl disable --now phobos-tcp >/dev/null 2>&1 || true
+    rm -f /etc/systemd/system/phobos-tcp.service
+    systemctl daemon-reload
+    echo "tcp fallback: disabled"
+}
+
+status() {
+    printf '{"enabled": %s, "port": "%s"}\n' \
+        "$(systemctl is-active -q phobos-tcp && echo true || echo false)" "$(env_get TCP_PORT)"
+}
+
+case "${1:-status}" in
+    enable)  enable "${2:-}" ;;
+    disable) disable ;;
+    status)  status ;;
+    *) echo "usage: $0 enable [port]|disable|status"; exit 2 ;;
+esac
--- a/udptcp/README.md
+++ b/udptcp/README.md
@@ -0,0 +1,6 @@
+# udptcp — резервный TCP-канал PCA Phobos
+
+UDP-пакеты (уже обфусцированные) внутри TCP: кадр = 2 байта длины + пакет.
+- сервер: `udptcp -s 0.0.0.0:443 127.0.0.1:2083` (служба `phobos-tcp`, порт в server.env `TCP_PORT`);
+- клиент: `udptcp -c 127.0.0.1:13256 <сервер>:443`, обфускатор клиента шлёт на 127.0.0.1:13256.
+Сборка: `gcc -O2 -static -pthread -o bin/udptcp-x86_64 udptcp.c` (+ aarch64-linux-gnu-gcc), Android — NDK (см. android-client/README.md).
--- a/udptcp/bin/udptcp-aarch64
+++ b/udptcp/bin/udptcp-aarch64
--- a/udptcp/bin/udptcp-x86_64
+++ b/udptcp/bin/udptcp-x86_64
--- a/udptcp/udptcp.c
+++ b/udptcp/udptcp.c
@@ -0,0 +1,175 @@
+/*
+ * udptcp — PCA Phobos fallback transport: UDP datagrams carried over TCP.
+ * Frames on the TCP stream: 2-byte big-endian length + payload.
+ *
+ *   server:  udptcp -s <listen_ip:port> <udp_target_ip:port>
+ *            each TCP connection gets its own UDP socket to the target
+ *            (the local wg-obfuscator), so the obfuscator sees one client per conn.
+ *   client:  udptcp -c <local_udp_ip:port> <tcp_server_host:port>
+ *            local UDP peer (client wg-obfuscator) <-> one TCP connection, reconnects.
+ *
+ * Plain C, no deps: builds for Linux servers, Android (NDK) and iOS.
+ */
+#include <arpa/inet.h>
+#include <errno.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <poll.h>
+#include <pthread.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <time.h>
+#include <unistd.h>
+
+#define MAXPKT 65535
+
+static int parse_addr(const char *s, struct sockaddr_storage *ss, socklen_t *len, int socktype) {
+    char host[256];
+    const char *colon = strrchr(s, ':');
+    if (!colon || colon == s || (size_t)(colon - s) >= sizeof host) return -1;
+    memcpy(host, s, colon - s);
+    host[colon - s] = 0;
+    struct addrinfo hints = {0}, *res;
+    hints.ai_family = AF_UNSPEC;
+    hints.ai_socktype = socktype;
+    if (getaddrinfo(host, colon + 1, &hints, &res) != 0) return -1;
+    memcpy(ss, res->ai_addr, res->ai_addrlen);
+    *len = res->ai_addrlen;
+    freeaddrinfo(res);
+    return 0;
+}
+
+static int read_full(int fd, unsigned char *buf, size_t n) {
+    size_t got = 0;
+    while (got < n) {
+        ssize_t r = read(fd, buf + got, n - got);
+        if (r <= 0) return -1;
+        got += (size_t)r;
+    }
+    return 0;
+}
+
+static int write_frame(int fd, const unsigned char *p, size_t n) {
+    unsigned char hdr[2] = {(unsigned char)(n >> 8), (unsigned char)(n & 0xff)};
+    if (write(fd, hdr, 2) != 2) return -1;
+    size_t sent = 0;
+    while (sent < n) {
+        ssize_t w = write(fd, p + sent, n - sent);
+        if (w <= 0) return -1;
+        sent += (size_t)w;
+    }
+    return 0;
+}
+
+static void tune_tcp(int fd) {
+    int one = 1;
+    setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one, sizeof one);
+    setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE, &one, sizeof one);
+}
+
+/* ── server ─────────────────────────────────────────────────────────────── */
+static struct sockaddr_storage g_target;
+static socklen_t g_target_len;
+
+static void *serve_conn(void *arg) {
+    int tcp = (int)(long)arg;
+    unsigned char buf[MAXPKT + 2];
+    int udp = socket(g_target.ss_family, SOCK_DGRAM, 0);
+    if (udp < 0 || connect(udp, (struct sockaddr *)&g_target, g_target_len) < 0) goto out;
+    tune_tcp(tcp);
+    struct pollfd p[2] = {{tcp, POLLIN, 0}, {udp, POLLIN, 0}};
+    for (;;) {
+        if (poll(p, 2, 300000) <= 0) break;            /* 5 min idle -> drop */
+        if (p[0].revents & (POLLIN | POLLHUP | POLLERR)) {
+            unsigned char h[2];
+            if (read_full(tcp, h, 2) < 0) break;
+            size_t n = ((size_t)h[0] << 8) | h[1];
+            if (n == 0 || read_full(tcp, buf, n) < 0) break;
+            send(udp, buf, n, 0);
+        }
+        if (p[1].revents & POLLIN) {
+            ssize_t n = recv(udp, buf, MAXPKT, 0);
+            if (n > 0 && write_frame(tcp, buf, (size_t)n) < 0) break;
+        }
+    }
+out:
+    if (udp >= 0) close(udp);
+    close(tcp);
+    return NULL;
+}
+
+static int run_server(const char *listen_s, const char *target_s) {
+    struct sockaddr_storage la; socklen_t ll;
+    if (parse_addr(listen_s, &la, &ll, SOCK_STREAM) || parse_addr(target_s, &g_target, &g_target_len, SOCK_DGRAM)) {
+        fprintf(stderr, "bad address\n"); return 2;
+    }
+    int ls = socket(la.ss_family, SOCK_STREAM, 0), one = 1;
+    setsockopt(ls, SOL_SOCKET, SO_REUSEADDR, &one, sizeof one);
+    if (bind(ls, (struct sockaddr *)&la, ll) < 0 || listen(ls, 128) < 0) { perror("listen"); return 1; }
+    fprintf(stderr, "udptcp server %s -> udp %s\n", listen_s, target_s);
+    for (;;) {
+        int c = accept(ls, NULL, NULL);
+        if (c < 0) { if (errno == EINTR) continue; perror("accept"); sleep(1); continue; }
+        pthread_t t;
+        if (pthread_create(&t, NULL, serve_conn, (void *)(long)c) == 0) pthread_detach(t);
+        else close(c);
+    }
+}
+
+/* ── client ─────────────────────────────────────────────────────────────── */
+static int connect_tcp(const char *server_s) {
+    struct sockaddr_storage sa; socklen_t sl;
+    if (parse_addr(server_s, &sa, &sl, SOCK_STREAM)) return -1;   /* re-resolve each time */
+    int s = socket(sa.ss_family, SOCK_STREAM, 0);
+    if (s < 0) return -1;
+    if (connect(s, (struct sockaddr *)&sa, sl) < 0) { close(s); return -1; }
+    tune_tcp(s);
+    return s;
+}
+
+static int run_client(const char *local_s, const char *server_s) {
+    struct sockaddr_storage la, peer; socklen_t ll, pl = 0;
+    if (parse_addr(local_s, &la, &ll, SOCK_DGRAM)) { fprintf(stderr, "bad address\n"); return 2; }
+    int us = socket(la.ss_family, SOCK_DGRAM, 0);
+    if (bind(us, (struct sockaddr *)&la, ll) < 0) { perror("bind"); return 1; }
+    fprintf(stderr, "udptcp client udp %s -> tcp %s\n", local_s, server_s);
+    unsigned char buf[MAXPKT + 2];
+    int tcp = -1;
+    time_t last_try = 0;
+    for (;;) {
+        struct pollfd p[2] = {{us, POLLIN, 0}, {tcp, POLLIN, 0}};
+        poll(p, tcp >= 0 ? 2 : 1, 1000);
+        if (p[0].revents & POLLIN) {
+            pl = sizeof peer;
+            ssize_t n = recvfrom(us, buf, MAXPKT, 0, (struct sockaddr *)&peer, &pl);
+            if (n > 0) {
+                if (tcp < 0 && time(NULL) != last_try) {
+                    last_try = time(NULL);
+                    tcp = connect_tcp(server_s);
+                    fprintf(stderr, tcp >= 0 ? "connected\n" : "connect failed\n");
+                }
+                if (tcp >= 0 && write_frame(tcp, buf, (size_t)n) < 0) { close(tcp); tcp = -1; }
+            }
+        }
+        if (tcp >= 0 && (p[1].revents & (POLLIN | POLLHUP | POLLERR))) {
+            unsigned char h[2];
+            if (read_full(tcp, h, 2) < 0) { close(tcp); tcp = -1; continue; }
+            size_t n = ((size_t)h[0] << 8) | h[1];
+            if (n == 0 || read_full(tcp, buf, n) < 0) { close(tcp); tcp = -1; continue; }
+            if (pl) sendto(us, buf, n, 0, (struct sockaddr *)&peer, pl);
+        }
+    }
+}
+
+int main(int argc, char **argv) {
+    signal(SIGPIPE, SIG_IGN);
+    if (argc == 4 && !strcmp(argv[1], "-s")) return run_server(argv[2], argv[3]);
+    if (argc == 4 && !strcmp(argv[1], "-c")) return run_client(argv[2], argv[3]);
+    fprintf(stderr, "usage: udptcp -s <listen ip:port> <udp target ip:port>\n"
+                    "       udptcp -c <local udp ip:port> <tcp server host:port>\n");
+    return 2;
+}
--- a/update.sh
+++ b/update.sh
@@ -86,10 +86,25 @@ $PHOBOS_DIR/server/phobos-cascade.sh|server/phobos-cascade.sh
 $PHOBOS_DIR/server/phobos-domain.sh|server/phobos-domain.sh
 $PHOBOS_DIR/server/phobos-limit.sh|server/phobos-limit.sh
 $PHOBOS_DIR/server/phobos-speedtest.sh|server/phobos-speedtest.sh
+$PHOBOS_DIR/server/phobos-tcp.sh|server/phobos-tcp.sh
 $PHOBOS_DIR/server/update.sh|update.sh
 LIST
 }

+ensure_tcp_fallback() {  # $1=ref ; primary only (secondaries have no panel)
+    [ -f "$PANEL_DIR/app.py" ] || return 0
+    local arch tmp
+    arch=$(uname -m); case "$arch" in amd64) arch=x86_64;; arm64) arch=aarch64;; esac
+    tmp=$(mktemp)
+    if fetch_repo_file "$1" "udptcp/bin/udptcp-$arch" "$tmp" && [ -s "$tmp" ]; then
+        install -m755 "$tmp" "$PHOBOS_DIR/bin/udptcp"
+    fi
+    rm -f "$tmp"
+    [ -x "$PHOBOS_DIR/server/phobos-tcp.sh" ] && ln -sf "$PHOBOS_DIR/server/phobos-tcp.sh" /usr/local/bin/phobos-tcp
+    [ -x "$PHOBOS_DIR/bin/udptcp" ] && "$PHOBOS_DIR/server/phobos-tcp.sh" enable >/dev/null 2>&1 \
+        && echo "TCP fallback: port $(grep '^TCP_PORT=' "$PHOBOS_DIR/server/server.env" | cut -d= -f2)" || true
+}
+
 run_self_check() {
    if [ -x "$PHOBOS_DIR/server/phobos-self-check.sh" ]; then
        ln -sf "$PHOBOS_DIR/server/phobos-self-check.sh" /usr/local/bin/phobos-self-check 2>/dev/null || true
@@ -251,6 +266,7 @@ case "${1:-}" in
    apply_ref "$ref"
    ensure_runtime_deps
    run_self_check
+    ensure_tcp_fallback "$ref"
    refresh_router_packages
    echo "$target" > "$VERFILE"
    restart_panel_service
@@ -1 +1 @@
 .4.0
 .4.1