Support OOB and add custom fake SNI

app/src/main/cpp/native-lib.c

@@ -13,14 +13,22 @@ const enum demode DESYNC_METHODS[] = {
         DESYNC_NONE,
         DESYNC_SPLIT,
         DESYNC_DISORDER,
-        DESYNC_FAKE
+        DESYNC_FAKE,
+        DESYNC_OOB,
 };
 
 extern int NOT_EXIT;
-extern struct packet fake_tls, fake_http;
+
 extern int get_default_ttl();
+
 extern int get_addr(const char *str, struct sockaddr_ina *addr);
 
+JNIEXPORT jint JNICALL
+Java_io_github_dovecoteescapee_byedpi_core_ByeDpiProxy_00024Companion_jniInit(JNIEnv *env, jobject thiz) {
+    oob_data.data = NULL;
+    return 0;
+}
+
 JNIEXPORT jint JNICALL
 Java_io_github_dovecoteescapee_byedpi_core_ByeDpiProxy_jniCreateSocket(
         JNIEnv *env,
@@ -36,6 +44,8 @@ Java_io_github_dovecoteescapee_byedpi_core_ByeDpiProxy_jniCreateSocket(
         jint split_position,
         jboolean split_at_host,
         jint fake_ttl,
+        jstring fake_sni,
+        jstring custom_oob_data,
         jboolean host_mixed_case,
         jboolean domain_mixed_case,
         jboolean host_remove_spaces,
@@ -52,6 +62,8 @@ Java_io_github_dovecoteescapee_byedpi_core_ByeDpiProxy_jniCreateSocket(
     if (get_addr(address, &s) < 0) {
         return -1;
     }
+    (*env)->ReleaseStringUTFChars(env, ip, address);
+
     s.in.sin_port = htons(port);
 
     params.max_open = max_connections;
@@ -83,6 +95,34 @@ Java_io_github_dovecoteescapee_byedpi_core_ByeDpiProxy_jniCreateSocket(
         return get_e();
     }
 
+    if (params.attack == DESYNC_FAKE) {
+        const char *sni = (*env)->GetStringUTFChars(env, fake_sni, 0);
+        LOG(LOG_S, "fake_sni: %s", sni);
+        int res = change_tls_sni(sni, fake_tls.data, fake_tls.size);
+        (*env)->ReleaseStringUTFChars(env, fake_sni, sni);
+        if (res) {
+            fprintf(stderr, "error chsni\n");
+            return -1;
+        }
+    }
+
+    if (params.attack == DESYNC_OOB) {
+        const char *oob = (*env)->GetStringUTFChars(env, custom_oob_data, 0);
+        const size_t oob_len = strlen(oob);
+        LOG(LOG_L, "custom_oob_data: %s", oob);
+        oob_data.size = oob_len;
+        LOG(LOG_L, "before free");
+        free(oob_data.data);
+        LOG(LOG_L, "after free");
+        oob_data.data = malloc(oob_len);
+        if (oob_data.data == NULL) {
+            uniperror("malloc");
+            return -1;
+        }
+        memcpy(oob_data.data, oob, oob_len);
+        (*env)->ReleaseStringUTFChars(env, custom_oob_data, oob);
+    }
+
     LOG(LOG_S, "listen_socket, fd: %d", fd);
     return fd;
 }
@@ -106,4 +146,4 @@ Java_io_github_dovecoteescapee_byedpi_core_ByeDpiProxy_jniStopProxy(JNIEnv *env,
         return get_e();
     }
     return 0;
-}
+}

app/src/main/java/io/github/dovecoteescapee/byedpi/core/ByeDpiProxy.kt

@@ -8,7 +8,10 @@ class ByeDpiProxy {
     companion object {
         init {
             System.loadLibrary("byedpi")
+            jniInit()
         }
+
+        private external fun jniInit(): Int
     }
 
     private val mutex = Mutex()
@@ -49,6 +52,8 @@ class ByeDpiProxy {
                 splitPosition = preferences.splitPosition,
                 splitAtHost = preferences.splitAtHost,
                 fakeTtl = preferences.fakeTtl,
+                fakeSni = preferences.fakeSni,
+                oobData = preferences.oobData,
                 hostMixedCase = preferences.hostMixedCase,
                 domainMixedCase = preferences.domainMixedCase,
                 hostRemoveSpaces = preferences.hostRemoveSpaces,
@@ -77,6 +82,8 @@ class ByeDpiProxy {
         splitPosition: Int,
         splitAtHost: Boolean,
         fakeTtl: Int,
+        fakeSni: String,
+        oobData: String,
         hostMixedCase: Boolean,
         domainMixedCase: Boolean,
         hostRemoveSpaces: Boolean,

app/src/main/java/io/github/dovecoteescapee/byedpi/core/ByeDpiProxyPreferences.kt

@@ -14,6 +14,8 @@ class ByeDpiProxyPreferences(
     splitPosition: Int? = null,
     splitAtHost: Boolean? = null,
     fakeTtl: Int? = null,
+    fakeSni: String? = null,
+    oobData: String? = null,
     hostMixedCase: Boolean? = null,
     domainMixedCase: Boolean? = null,
     hostRemoveSpaces: Boolean? = null,
@@ -32,6 +34,8 @@ class ByeDpiProxyPreferences(
     val splitPosition: Int = splitPosition ?: 3
     val splitAtHost: Boolean = splitAtHost ?: false
     val fakeTtl: Int = fakeTtl ?: 8
+    val fakeSni: String = fakeSni ?: "www.w3c.org"
+    val oobData: String = oobData ?: "a"
     val hostMixedCase: Boolean = hostMixedCase ?: false
     val domainMixedCase: Boolean = domainMixedCase ?: false
     val hostRemoveSpaces: Boolean = hostRemoveSpaces ?: false
@@ -52,6 +56,8 @@ class ByeDpiProxyPreferences(
         splitPosition = preferences.getString("byedpi_split_position", null)?.toIntOrNull(),
         splitAtHost = preferences.getBoolean("byedpi_split_at_host", false),
         fakeTtl = preferences.getString("byedpi_fake_ttl", null)?.toIntOrNull(),
+        fakeSni = preferences.getString("byedpi_fake_sni", null),
+        oobData = preferences.getString("byedpi_oob_data", null),
         hostMixedCase = preferences.getBoolean("byedpi_host_mixed_case", false),
         domainMixedCase = preferences.getBoolean("byedpi_domain_mixed_case", false),
         hostRemoveSpaces = preferences.getBoolean("byedpi_host_remove_spaces", false),
@@ -64,7 +70,8 @@ class ByeDpiProxyPreferences(
         None,
         Split,
         Disorder,
-        Fake;
+        Fake,
+        OOB;
 
         companion object {
             fun fromName(name: String): DesyncMethod {
@@ -73,6 +80,7 @@ class ByeDpiProxyPreferences(
                     "split" -> Split
                     "disorder" -> Disorder
                     "fake" -> Fake
+                    "oob" -> OOB
                     else -> throw IllegalArgumentException("Unknown desync method: $name")
                 }
             }

app/src/main/res/values/arrays.xml

@@ -25,11 +25,13 @@
         <item name="split">Split</item>
         <item name="disorder">Disorder</item>
         <item name="fake">Fake</item>
+        <item name="oob">Out-of-band</item>
     </array>
     <array name="byedpi_desync_methods_entries">
         <item name="none">none</item>
         <item name="split">split</item>
         <item name="disorder">disorder</item>
         <item name="fake">fake</item>
+        <item name="oob">oob</item>
     </array>
 </resources>

app/src/main/res/values/strings.xml

@@ -49,4 +49,7 @@
     <string name="notification_title">ByeDPI</string>
     <string name="vpn_notification_content">VPN is running</string>
     <string name="proxy_notification_content">Proxy is running</string>
+    <string name="general_category">General</string>
+    <string name="byedpi_category">ByeDPI</string>
+    <string name="about_category">About</string>
 </resources>

app/src/main/res/xml/settings.xml

@@ -4,8 +4,8 @@
     xmlns:tools="http://schemas.android.com/tools"
     android:tag="settings_screen">
 
-    <PreferenceCategory
-        android:title="General">
+    <androidx.preference.PreferenceCategory
+        android:title="@string/general_category">
 
         <DropDownPreference
             android:key="app_theme"
@@ -23,10 +23,10 @@
             android:defaultValue="vpn"
             app:useSimpleSummaryProvider="true" />
 
-    </PreferenceCategory>
+    </androidx.preference.PreferenceCategory>
 
-    <PreferenceCategory
-        android:title="ByeDPI">
+    <androidx.preference.PreferenceCategory
+        android:title="@string/byedpi_category">
 
         <Preference
             android:key="byedpi_readme"
@@ -115,6 +115,18 @@
             android:defaultValue="8"
             app:useSimpleSummaryProvider="true" />
 
+        <com.takisoft.preferencex.EditTextPreference
+            android:key="byedpi_fake_sni"
+            android:title="SNI of fake packet"
+            android:defaultValue="www.w3c.org"
+            app:useSimpleSummaryProvider="true" />
+
+        <com.takisoft.preferencex.EditTextPreference
+            android:key="byedpi_oob_data"
+            android:title="OOB Data"
+            android:defaultValue="a"
+            app:useSimpleSummaryProvider="true" />
+
         <CheckBoxPreference
             android:key="byedpi_host_mixed_case"
             android:title="@string/byedpi_host_mixed_case_setting"
@@ -147,10 +159,10 @@
             android:title="@string/byedpi_tlsrec_at_sni_setting"
             android:defaultValue="false" />
 
-    </PreferenceCategory>
+    </androidx.preference.PreferenceCategory>
 
-    <PreferenceCategory
-        android:title="About">
+    <androidx.preference.PreferenceCategory
+        android:title="@string/about_category">
 
         <Preference
             android:key="version"
@@ -167,6 +179,6 @@
                 android:data="https://github.com/dovecoteescapee/ByeDPIAndroid" />
         </Preference>
 
-    </PreferenceCategory>
+    </androidx.preference.PreferenceCategory>
 
 </PreferenceScreen>