Merge pull request #1088 from amnezia-vpn/bugfix/android-native-wg-obfuscation

Add support for obfuscated WG on Android

client/android/awg/src/main/kotlin/Awg.kt

@@ -1,28 +1,21 @@
 package org.amnezia.vpn.protocol.awg
 
 import org.amnezia.vpn.protocol.wireguard.Wireguard
-import org.amnezia.vpn.util.optStringOrNull
+import org.amnezia.vpn.protocol.wireguard.WireguardConfig
 import org.json.JSONObject
 
 class Awg : Wireguard() {
 
     override val ifName: String = "awg0"
 
-    override fun parseConfig(config: JSONObject): AwgConfig {
+    override fun parseConfig(config: JSONObject): WireguardConfig {
         val configData = config.getJSONObject("awg_config_data")
-        return AwgConfig.build {
+        return WireguardConfig.build {
+            setUseProtocolExtension(true)
+            configExtensionParameters(configData)
             configWireguard(config, configData)
             configSplitTunneling(config)
             configAppSplitTunneling(config)
-            configData.optStringOrNull("Jc")?.let { setJc(it.toInt()) }
-            configData.optStringOrNull("Jmin")?.let { setJmin(it.toInt()) }
-            configData.optStringOrNull("Jmax")?.let { setJmax(it.toInt()) }
-            configData.optStringOrNull("S1")?.let { setS1(it.toInt()) }
-            configData.optStringOrNull("S2")?.let { setS2(it.toInt()) }
-            configData.optStringOrNull("H1")?.let { setH1(it.toLong()) }
-            configData.optStringOrNull("H2")?.let { setH2(it.toLong()) }
-            configData.optStringOrNull("H3")?.let { setH3(it.toLong()) }
-            configData.optStringOrNull("H4")?.let { setH4(it.toLong()) }
         }
     }
 }

client/android/awg/src/main/kotlin/AwgConfig.kt

@@ -1,108 +0,0 @@
-package org.amnezia.vpn.protocol.awg
-
-import org.amnezia.vpn.protocol.BadConfigException
-import org.amnezia.vpn.protocol.wireguard.WireguardConfig
-
-class AwgConfig private constructor(
-    wireguardConfigBuilder: WireguardConfig.Builder,
-    val jc: Int,
-    val jmin: Int,
-    val jmax: Int,
-    val s1: Int,
-    val s2: Int,
-    val h1: Long,
-    val h2: Long,
-    val h3: Long,
-    val h4: Long
-) : WireguardConfig(wireguardConfigBuilder) {
-
-    private constructor(builder: Builder) : this(
-        builder,
-        builder.jc,
-        builder.jmin,
-        builder.jmax,
-        builder.s1,
-        builder.s2,
-        builder.h1,
-        builder.h2,
-        builder.h3,
-        builder.h4
-    )
-
-    override fun appendDeviceLine(sb: StringBuilder) = with(sb) {
-        super.appendDeviceLine(this)
-        appendLine("jc=$jc")
-        appendLine("jmin=$jmin")
-        appendLine("jmax=$jmax")
-        appendLine("s1=$s1")
-        appendLine("s2=$s2")
-        appendLine("h1=$h1")
-        appendLine("h2=$h2")
-        appendLine("h3=$h3")
-        appendLine("h4=$h4")
-    }
-
-    class Builder : WireguardConfig.Builder() {
-
-        private var _jc: Int? = null
-        internal var jc: Int
-            get() = _jc ?: throw BadConfigException("AWG: parameter jc is undefined")
-            private set(value) { _jc = value }
-
-        private var _jmin: Int? = null
-        internal var jmin: Int
-            get() = _jmin ?: throw BadConfigException("AWG: parameter jmin is undefined")
-            private set(value) { _jmin = value }
-
-        private var _jmax: Int? = null
-        internal var jmax: Int
-            get() = _jmax ?: throw BadConfigException("AWG: parameter jmax is undefined")
-            private set(value) { _jmax = value }
-
-        private var _s1: Int? = null
-        internal var s1: Int
-            get() = _s1 ?: throw BadConfigException("AWG: parameter s1 is undefined")
-            private set(value) { _s1 = value }
-
-        private var _s2: Int? = null
-        internal var s2: Int
-            get() = _s2 ?: throw BadConfigException("AWG: parameter s2 is undefined")
-            private set(value) { _s2 = value }
-
-        private var _h1: Long? = null
-        internal var h1: Long
-            get() = _h1 ?: throw BadConfigException("AWG: parameter h1 is undefined")
-            private set(value) { _h1 = value }
-
-        private var _h2: Long? = null
-        internal var h2: Long
-            get() = _h2 ?: throw BadConfigException("AWG: parameter h2 is undefined")
-            private set(value) { _h2 = value }
-
-        private var _h3: Long? = null
-        internal var h3: Long
-            get() = _h3 ?: throw BadConfigException("AWG: parameter h3 is undefined")
-            private set(value) { _h3 = value }
-
-        private var _h4: Long? = null
-        internal var h4: Long
-            get() = _h4 ?: throw BadConfigException("AWG: parameter h4 is undefined")
-            private set(value) { _h4 = value }
-
-        fun setJc(jc: Int) = apply { this.jc = jc }
-        fun setJmin(jmin: Int) = apply { this.jmin = jmin }
-        fun setJmax(jmax: Int) = apply { this.jmax = jmax }
-        fun setS1(s1: Int) = apply { this.s1 = s1 }
-        fun setS2(s2: Int) = apply { this.s2 = s2 }
-        fun setH1(h1: Long) = apply { this.h1 = h1 }
-        fun setH2(h2: Long) = apply { this.h2 = h2 }
-        fun setH3(h3: Long) = apply { this.h3 = h3 }
-        fun setH4(h4: Long) = apply { this.h4 = h4 }
-
-        override fun build(): AwgConfig = configBuild().run { AwgConfig(this@Builder) }
-    }
-
-    companion object {
-        inline fun build(block: Builder.() -> Unit): AwgConfig = Builder().apply(block).build()
-    }
-}

client/android/wireguard/src/main/kotlin/org/amnezia/vpn/protocol/wireguard/Wireguard.kt

@@ -129,12 +129,29 @@ open class Wireguard : Protocol() {
         val port = configData.getInt("port")
         setEndpoint(InetEndpoint(host, port))
 
+        if (configData.optBoolean("isObfuscationEnabled")) {
+            setUseProtocolExtension(true)
+            configExtensionParameters(configData)
+        }
+
         configData.optStringOrNull("persistent_keep_alive")?.let { setPersistentKeepalive(it.toInt()) }
         configData.getString("client_priv_key").let { setPrivateKeyHex(it.base64ToHex()) }
         configData.getString("server_pub_key").let { setPublicKeyHex(it.base64ToHex()) }
         configData.optStringOrNull("psk_key")?.let { setPreSharedKeyHex(it.base64ToHex()) }
     }
 
+    protected fun WireguardConfig.Builder.configExtensionParameters(configData: JSONObject) {
+        configData.optStringOrNull("Jc")?.let { setJc(it.toInt()) }
+        configData.optStringOrNull("Jmin")?.let { setJmin(it.toInt()) }
+        configData.optStringOrNull("Jmax")?.let { setJmax(it.toInt()) }
+        configData.optStringOrNull("S1")?.let { setS1(it.toInt()) }
+        configData.optStringOrNull("S2")?.let { setS2(it.toInt()) }
+        configData.optStringOrNull("H1")?.let { setH1(it.toLong()) }
+        configData.optStringOrNull("H2")?.let { setH2(it.toLong()) }
+        configData.optStringOrNull("H3")?.let { setH3(it.toLong()) }
+        configData.optStringOrNull("H4")?.let { setH4(it.toLong()) }
+    }
+
     private fun start(config: WireguardConfig, vpnBuilder: Builder, protect: (Int) -> Boolean) {
         if (tunnelHandle != -1) {
             Log.w(TAG, "Tunnel already up")

client/android/wireguard/src/main/kotlin/org/amnezia/vpn/protocol/wireguard/WireguardConfig.kt

@@ -1,6 +1,7 @@
 package org.amnezia.vpn.protocol.wireguard
 
 import android.util.Base64
+import org.amnezia.vpn.protocol.BadConfigException
 import org.amnezia.vpn.protocol.ProtocolConfig
 import org.amnezia.vpn.util.net.InetEndpoint
 
@@ -12,7 +13,17 @@ open class WireguardConfig protected constructor(
     val persistentKeepalive: Int,
     val publicKeyHex: String,
     val preSharedKeyHex: String?,
-    val privateKeyHex: String
+    val privateKeyHex: String,
+    val useProtocolExtension: Boolean,
+    val jc: Int?,
+    val jmin: Int?,
+    val jmax: Int?,
+    val s1: Int?,
+    val s2: Int?,
+    val h1: Long?,
+    val h2: Long?,
+    val h3: Long?,
+    val h4: Long?
 ) : ProtocolConfig(protocolConfigBuilder) {
 
     protected constructor(builder: Builder) : this(
@@ -21,7 +32,17 @@ open class WireguardConfig protected constructor(
         builder.persistentKeepalive,
         builder.publicKeyHex,
         builder.preSharedKeyHex,
-        builder.privateKeyHex
+        builder.privateKeyHex,
+        builder.useProtocolExtension,
+        builder.jc,
+        builder.jmin,
+        builder.jmax,
+        builder.s1,
+        builder.s2,
+        builder.h1,
+        builder.h2,
+        builder.h3,
+        builder.h4
     )
 
     fun toWgUserspaceString(): String = with(StringBuilder()) {
@@ -33,6 +54,30 @@ open class WireguardConfig protected constructor(
 
     open fun appendDeviceLine(sb: StringBuilder) = with(sb) {
         appendLine("private_key=$privateKeyHex")
+        if (useProtocolExtension) {
+            validateProtocolExtensionParameters()
+            appendLine("jc=$jc")
+            appendLine("jmin=$jmin")
+            appendLine("jmax=$jmax")
+            appendLine("s1=$s1")
+            appendLine("s2=$s2")
+            appendLine("h1=$h1")
+            appendLine("h2=$h2")
+            appendLine("h3=$h3")
+            appendLine("h4=$h4")
+        }
+    }
+
+    private fun validateProtocolExtensionParameters() {
+        if (jc == null) throw BadConfigException("Parameter jc is undefined")
+        if (jmin == null) throw BadConfigException("Parameter jmin is undefined")
+        if (jmax == null) throw BadConfigException("Parameter jmax is undefined")
+        if (s1 == null) throw BadConfigException("Parameter s1 is undefined")
+        if (s2 == null) throw BadConfigException("Parameter s2 is undefined")
+        if (h1 == null) throw BadConfigException("Parameter h1 is undefined")
+        if (h2 == null) throw BadConfigException("Parameter h2 is undefined")
+        if (h3 == null) throw BadConfigException("Parameter h3 is undefined")
+        if (h4 == null) throw BadConfigException("Parameter h4 is undefined")
     }
 
     open fun appendPeerLine(sb: StringBuilder) = with(sb) {
@@ -65,6 +110,18 @@ open class WireguardConfig protected constructor(
 
         override var mtu: Int = WIREGUARD_DEFAULT_MTU
 
+        internal var useProtocolExtension: Boolean = false
+
+        internal var jc: Int? = null
+        internal var jmin: Int? = null
+        internal var jmax: Int? = null
+        internal var s1: Int? = null
+        internal var s2: Int? = null
+        internal var h1: Long? = null
+        internal var h2: Long? = null
+        internal var h3: Long? = null
+        internal var h4: Long? = null
+
         fun setEndpoint(endpoint: InetEndpoint) = apply { this.endpoint = endpoint }
 
         fun setPersistentKeepalive(persistentKeepalive: Int) = apply { this.persistentKeepalive = persistentKeepalive }
@@ -75,6 +132,18 @@ open class WireguardConfig protected constructor(
 
         fun setPrivateKeyHex(privateKeyHex: String) = apply { this.privateKeyHex = privateKeyHex }
 
+        fun setUseProtocolExtension(useProtocolExtension: Boolean) = apply { this.useProtocolExtension = useProtocolExtension }
+
+        fun setJc(jc: Int) = apply { this.jc = jc }
+        fun setJmin(jmin: Int) = apply { this.jmin = jmin }
+        fun setJmax(jmax: Int) = apply { this.jmax = jmax }
+        fun setS1(s1: Int) = apply { this.s1 = s1 }
+        fun setS2(s2: Int) = apply { this.s2 = s2 }
+        fun setH1(h1: Long) = apply { this.h1 = h1 }
+        fun setH2(h2: Long) = apply { this.h2 = h2 }
+        fun setH3(h3: Long) = apply { this.h3 = h3 }
+        fun setH4(h4: Long) = apply { this.h4 = h4 }
+
         override fun build(): WireguardConfig = configBuild().run { WireguardConfig(this@Builder) }
     }