开发NDK时,为保存你的so文件不被拿去反调试,可以添加应用签名校验

checksign.hpp

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#ifndef checksign_hpp
#define checksign_hpp

#include <stdio.h>
#include <jni.h>
static const char *app_packageName = "com.uilucky.demo";
static const int app_signature_hash_code = 1985487779;
static const char *RELEASE_SIGN = "78454545454545454545555555555555555555555555555555555...";
jobject getApplication(JNIEnv *env);
/*
 校验APP签名是否一致
 返回值为1 表示合法
 */
jint check_sing(JNIEnv *env);

#endif /* checksign_hpp */

checksign.cpp

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#include "checksign.hpp"
#include <iostream>
jobject getApplication(JNIEnv *env) {
    jobject application = NULL;
    jclass activity_thread_clz = env->FindClass("android/app/ActivityThread");
    if (activity_thread_clz != NULL) {
        jmethodID currentApplication = env->GetStaticMethodID(
                                                              activity_thread_clz, "currentApplication", "()Landroid/app/Application;");
        if (currentApplication != NULL) {
            application = env->CallStaticObjectMethod(activity_thread_clz, currentApplication);
        }
    }
    return application;
}
jint check_sing(JNIEnv *env){
    jobject contextObject = getApplication(env);
    jclass native_class = env->GetObjectClass(contextObject);
    jmethodID pm_id = env->GetMethodID(native_class, "getPackageManager", "()Landroid/content/pm/PackageManager;");
    jobject pm_obj = env->CallObjectMethod(contextObject, pm_id);
    jclass pm_clazz = env->GetObjectClass(pm_obj);
    // 得到 getPackageInfo 方法的 ID
    jmethodID package_info_id = env->GetMethodID(pm_clazz, "getPackageInfo","(Ljava/lang/String;I)Landroid/content/pm/PackageInfo;");
    jclass native_classs = env->GetObjectClass(contextObject);
    jmethodID mId = env->GetMethodID(native_classs, "getPackageName", "()Ljava/lang/String;");
    jstring pkg_str = static_cast<jstring>(env->CallObjectMethod(contextObject, mId));
    // 获得应用包的信息
    jobject pi_obj = env->CallObjectMethod(pm_obj, package_info_id, pkg_str, 64);
    // 获得 PackageInfo 类
    jclass pi_clazz = env->GetObjectClass(pi_obj);
    // 获得签名数组属性的 ID
    jfieldID signatures_fieldId = env->GetFieldID(pi_clazz, "signatures", "[Landroid/content/pm/Signature;");
    jobject signatures_obj = env->GetObjectField(pi_obj, signatures_fieldId);
    jobjectArray signaturesArray = (jobjectArray)signatures_obj;
    jsize size = env->GetArrayLength(signaturesArray);
    jobject signature_obj = env->GetObjectArrayElement(signaturesArray, 0);
    jclass signature_clazz = env->GetObjectClass(signature_obj);
    jmethodID string_id = env->GetMethodID(signature_clazz, "toCharsString", "()Ljava/lang/String;");
    jstring str = static_cast<jstring>(env->CallObjectMethod(signature_obj, string_id));
    char *c_msg = (char*)env->GetStringUTFChars(str,0);
    //return str;
    if(strcmp(c_msg,RELEASE_SIGN)==0)//签名一致  返回合法的 api key，否则返回错误
    {
        return 1;
    }else
    {
        return 0;
    }
}

RELEASE_SIGN 获取方法,可以在android 中使用如下代码打印

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public static String getSignature(Context context)
    {
        try {
            /** 通过包管理器获得指定包名包含签名的包信息 **/
            PackageInfo packageInfo = context.getPackageManager().getPackageInfo(context.getPackageName(), PackageManager.GET_SIGNATURES);
            /******* 通过返回的包信息获得签名数组 *******/
            Signature[] signatures = packageInfo.signatures;
            /******* 循环遍历签名数组拼接应用签名 *******/
            return signatures[0].toCharsString();
            /************** 得到应用签名 **************/
        } catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
        }
        return null;
    }