jni 驗證apk簽名

char* RELEASE_SIGN = "your release sign";

JNIEXPORT jboolean JNICALL Java_edu_scnu_jsj_androidsecurity_jnis_JUtil_verifySign
        (JNIEnv *env, jobject, jobject contextObject, jint signHashCode) {

    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);
    //  getPackageInfo 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));
    // package info
    jobject pi_obj = env->CallObjectMethod(pm_obj, package_info_id, pkg_str, 64);
    //  PackageInfo calss
    jclass pi_clazz = env->GetObjectClass(pi_obj);
    // signature  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);


    //check out hashCode
    

    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);
    if (strcmp(c_msg, RELEASE_SIGN) == 0)//
    {
        return JNI_TRUE;
    }else {
        return JNI_FALSE;
    }  

}