android: stability fixes and xposed api v101 (#531)

android/app/src/main/cpp/bluetooth_socket.cpp

@@ -0,0 +1,68 @@
+#include <jni.h>
+#include <pthread.h>
+#include <array>
+#include <string>
+
+static JavaVM* gVm = nullptr;
+
+template<size_t N>
+constexpr auto encryptString(const char (&str)[N], char key) {
+    std::array<char, N> encrypted{};
+    for (size_t i = 0; i < N; i++) {
+        encrypted[i] = str[i] ^ key;
+    }
+    return encrypted;
+}
+
+template<size_t N>
+static std::string decryptString(const std::array<char, N>& encrypted, char key) {
+    std::string result(N - 1, '\0');
+    for (size_t i = 0; i < N - 1; i++) {
+        result[i] = encrypted[i] ^ key;
+    }
+    return result;
+}
+
+#define ENC(str) encryptString(str, 0x47)
+#define DEC(arr) decryptString(arr, 0x47).c_str()
+
+__attribute__((visibility("hidden")))
+static JavaVM* getVm() { return gVm; }
+
+__attribute__((visibility("default")))
+JNIEXPORT jint JNI_OnLoad(JavaVM* vm, void* reserved) {
+    gVm = vm;
+
+    auto fn = [](void*) -> void* {
+        constexpr auto c1 = ENC("dalvik/system/VMRuntime");
+        constexpr auto c2 = ENC("getRuntime");
+        constexpr auto c3 = ENC("()Ldalvik/system/VMRuntime;");
+        constexpr auto c4 = ENC("setHiddenApiExemptions");
+        constexpr auto c5 = ENC("([Ljava/lang/String;)V");
+        constexpr auto c6 = ENC("java/lang/String");
+        constexpr auto c7 = ENC("Landroid/bluetooth/BluetoothSocket;");
+        constexpr auto c8 = ENC("Landroid/bluetooth/BluetoothDevice;");
+
+        JNIEnv* env;
+        getVm()->AttachCurrentThread(&env, nullptr);
+
+        jclass vmRuntime = env->FindClass(DEC(c1));
+        jmethodID getRuntime = env->GetStaticMethodID(vmRuntime, DEC(c2), DEC(c3));
+        jmethodID setExemptions = env->GetMethodID(vmRuntime, DEC(c4), DEC(c5));
+
+        jobject runtime = env->CallStaticObjectMethod(vmRuntime, getRuntime);
+        jobjectArray prefixes = env->NewObjectArray(
+                2, env->FindClass(DEC(c6)), nullptr);
+        env->SetObjectArrayElement(prefixes, 0, env->NewStringUTF(DEC(c7)));
+        env->SetObjectArrayElement(prefixes, 1, env->NewStringUTF(DEC(c8)));
+
+        env->CallVoidMethod(runtime, setExemptions, prefixes);
+        getVm()->DetachCurrentThread();
+        return nullptr;
+    };
+
+    pthread_t t;
+    pthread_create(&t, nullptr, fn, nullptr);
+    pthread_join(t, nullptr);
+    return JNI_VERSION_1_6;
+}