只是普通的单机手游,广告比较多,所以分析处理了下,校验流程蛮有意思的,所以就分享出来了
样本进行了加固,对其dump出dex后重打包出现崩溃

ida分析地址发现为jni函数引起


利用Xposed直接替换该函数,崩溃问题解决
但是出现了新的问题,游戏卡在了加载页面


对该类的其他jni函数进行分析,发现supportVulkan很明显进行了签名读取,对其去除签名校验。
此处参考项目:ApkSignatureKillerEx
去除完签名校验后,游戏能正常进入主页面,但是点击游戏地图没有任何反应。
在对原包进行多次测试发现,在首次启动游戏时,如果断网也会出现无法正常进入地图的问题,怀疑是游戏首次启动进行了网络请求进行数据校验
经过抓包对比定位到可疑数据包

利用Frida的算法通杀脚本没有定位到相关内容,怀疑是so层进行了请求

通过调用栈可以很清晰看到请求是从unity引擎相关的so中发出的。
查阅资料,在unity中,网络请求主要通过UnityWebRequest 类来执行网络请求,利用frida-il2cpp-bridge对UnityWebRequest进行trace,打印调用栈得
在IDA中进行交叉引用分析定位到UnitySDKManager类
增加UnitySDKManager类重新对其trace(因为出现报错,把参数输出关了)
通过调用栈可以初步对校验流程进行了解,主要通过ServerVerifyApk函数进行校验,经过一系列字符串加解密,最后进行网络请求
对关键函数进行hook分析
发现之前抓包获得的请求体相对应,其中,appFileList还是密文,继续分析

与dump.cs中的函数进行对照发现v14 由字符串转hex转base64获得
hook HexStringToHex 函数获得参数
IDA继续查找调用发现其中字符串由GetFileInfoList函数获得
很明显,调用了libUnitySDK.so中的GetFileInfoList函数获得
FileInfoListStr在writeFileJson函数中被赋值,而writeFileJson则是由java函数上文中的IsHDR_DisplayBoot调用(该函数首个参数为base.apk路径)

很明显,ll11l1l1ll函数 对之前的明文字符串进行了加密,frida hook打印参数
其中 HashList 中文件对应的值为文件的 crc
至此,除了具体的字符串加密算法,游戏的校验流程已经很清晰
对该校验去除的思路:
ps.仅限于学习交流,切勿用于商业用途,若造成侵权,请联系作者处理。
样本链接:6d8K9s2c8@1M7s2y4Q4x3@1q4Q4x3V1k6Q4x3V1k6H3j5h3&6Q4x3X3g2T1j5h3W2V1N6g2)9J5k6h3y4G2L8g2)9J5c8Y4y4Q4x3V1j5I4j5i4N6i4h3f1y4r3x3X3&6f1y4e0m8I4f1q4u0B7z5q4)9#2k6V1y4d9N6q4)9J5k6p5q4Q4x3@1k6H3N6$3c8Q4x3@1c8V1z5s2N6F1
XposedHelpers.findAndHookMethod("com.unity3d.player.UnityPlayerActivity", classLoader, "IsHDR_DisplayBoot", java.lang.String.class, java.lang.String.class, new XC_MethodReplacement() {
@Override
protected Object replaceHookedMethod(MethodHookParam methodHookParam) throws Throwable {
return null;
}
});
XposedHelpers.findAndHookMethod("com.unity3d.player.UnityPlayerActivity", classLoader, "IsHDR_DisplayBoot", java.lang.String.class, java.lang.String.class, new XC_MethodReplacement() {
@Override
protected Object replaceHookedMethod(MethodHookParam methodHookParam) throws Throwable {
return null;
}
});
0x0247db9c ┌─UnityEngine.Networking.UnityWebRequest::.ctor(this = UnityEngine.Networking.UnityWebRequest, url = "65bK9s2c8@1M7q4)9K6b7g2)9J5c8W2)9J5c8U0p5H3y4W2)9J5k6e0f1@1i4K6u0W2x3e0V1@1i4K6u0W2x3e0j5%4i4K6y4m8z5o6l9%4y4#2)9J5c8V1y4Z5k6h3y4C8g2i4m8V1j5i4c8W2", method = "POST")
0x0247db00 │ ┌─UnityEngine.Networking.UnityWebRequest::set_url(this = UnityEngine.Networking.UnityWebRequest, value = "331K9s2c8@1M7q4)9K6b7g2)9J5c8W2)9J5c8U0p5H3y4W2)9J5k6e0f1@1i4K6u0W2x3e0V1@1i4K6u0W2x3e0j5%4i4K6y4m8z5o6l9%4y4#2)9J5c8V1y4Z5k6h3y4C8g2i4m8V1j5i4c8W2")
0x0247ef38 │ │ ┌─UnityEngine.Networking.UnityWebRequest::InternalSetUrl(this = UnityEngine.Networking.UnityWebRequest, url = "29aK9s2c8@1M7q4)9K6b7g2)9J5c8W2)9J5c8U0p5H3y4W2)9J5k6e0f1@1i4K6u0W2x3e0V1@1i4K6u0W2x3e0j5%4i4K6y4m8z5o6l9%4y4#2)9J5c8V1y4Z5k6h3y4C8g2i4m8V1j5i4c8W2")
0x0247ef38 │ │ └─UnityEngine.Networking.UnityWebRequest::InternalSetUrl
0x0247db00 │ └─UnityEngine.Networking.UnityWebRequest::set_url
0x0247dc1c │ ┌─UnityEngine.Networking.UnityWebRequest::set_method(this = UnityEngine.Networking.UnityWebRequest, value = "POST")
0x0247e4e0 │ │ ┌─UnityEngine.Networking.UnityWebRequest::InternalSetMethod(this = UnityEngine.Networking.UnityWebRequest, methodType = Post)
0x0247e4e0 │ │ └─UnityEngine.Networking.UnityWebRequest::InternalSetMethod
0x0247dc1c │ └─UnityEngine.Networking.UnityWebRequest::set_method
0x0247db9c └─UnityEngine.Networking.UnityWebRequest::.ctor
0x0247db9c ┌─UnityEngine.Networking.UnityWebRequest::.ctor(this = UnityEngine.Networking.UnityWebRequest, url = "eb3K9s2c8@1M7q4)9K6b7g2)9J5c8W2)9J5c8U0p5H3y4W2)9J5k6e0f1@1i4K6u0W2x3e0V1@1i4K6u0W2x3e0j5%4i4K6y4m8z5o6l9%4y4#2)9J5c8V1y4Z5k6h3y4C8g2i4m8V1j5i4c8W2", method = "POST")
0x0247db00 │ ┌─UnityEngine.Networking.UnityWebRequest::set_url(this = UnityEngine.Networking.UnityWebRequest, value = "a0fK9s2c8@1M7q4)9K6b7g2)9J5c8W2)9J5c8U0p5H3y4W2)9J5k6e0f1@1i4K6u0W2x3e0V1@1i4K6u0W2x3e0j5%4i4K6y4m8z5o6l9%4y4#2)9J5c8V1y4Z5k6h3y4C8g2i4m8V1j5i4c8W2")
0x0247ef38 │ │ ┌─UnityEngine.Networking.UnityWebRequest::InternalSetUrl(this = UnityEngine.Networking.UnityWebRequest, url = "435K9s2c8@1M7q4)9K6b7g2)9J5c8W2)9J5c8U0p5H3y4W2)9J5k6e0f1@1i4K6u0W2x3e0V1@1i4K6u0W2x3e0j5%4i4K6y4m8z5o6l9%4y4#2)9J5c8V1y4Z5k6h3y4C8g2i4m8V1j5i4c8W2")
0x0247ef38 │ │ └─UnityEngine.Networking.UnityWebRequest::InternalSetUrl
0x0247db00 │ └─UnityEngine.Networking.UnityWebRequest::set_url
0x0247dc1c │ ┌─UnityEngine.Networking.UnityWebRequest::set_method(this = UnityEngine.Networking.UnityWebRequest, value = "POST")
0x0247e4e0 │ │ ┌─UnityEngine.Networking.UnityWebRequest::InternalSetMethod(this = UnityEngine.Networking.UnityWebRequest, methodType = Post)
0x0247e4e0 │ │ └─UnityEngine.Networking.UnityWebRequest::InternalSetMethod
0x0247dc1c │ └─UnityEngine.Networking.UnityWebRequest::set_method
0x0247db9c └─UnityEngine.Networking.UnityWebRequest::.ctor
追踪调用定位到
class UnitySDK.UnitySDKManager.<PostData>d__25 : System.Object, System.Collections.Generic.IEnumerator<System.Object>, System.Collections.IEnumerator, System.IDisposable
private Boolean MoveNext() { }
追踪调用定位到
class UnitySDK.UnitySDKManager.<PostData>d__25 : System.Object, System.Collections.Generic.IEnumerator<System.Object>, System.Collections.IEnumerator, System.IDisposable
private Boolean MoveNext() { }
0x00b15b44 ┌─UnitySDK.UnitySDKManager::ServerVerifyApk
0x00b04b3c │ ┌─UnitySDK.UnitySDKManager::GetFileInfoList
0x00b04b3c │ └─UnitySDK.UnitySDKManager::GetFileInfoList
0x00b06ec0 │ ┌─UnitySDK.UnitySDKManager::GetGamePackageName
0x00b06ec0 │ └─UnitySDK.UnitySDKManager::GetGamePackageName
0x00b06204 │ ┌─UnitySDK.UnitySDKManager::GetSDKVersion
0x00b06204 │ └─UnitySDK.UnitySDKManager::GetSDKVersion
0x00b06278 │ ┌─UnitySDK.UnitySDKManager::HexStringToHex
0x00b06278 │ └─UnitySDK.UnitySDKManager::HexStringToHex
0x00b10fcc │ ┌─UnitySDK.UnitySDKManager::EncryptString
0x00b10fcc │ └─UnitySDK.UnitySDKManager::EncryptString
0x00b100a4 │ ┌─UnitySDK.UnitySDKManager::PostData
0x00a341fc │ │ ┌─UnitySDK.UnitySDKManager.<PostData>d__25::.ctor
0x00a341fc │ │ └─UnitySDK.UnitySDKManager.<PostData>d__25::.ctor
0x00b100a4 │ └─UnitySDK.UnitySDKManager::PostData
0x00a3422c │ ┌─UnitySDK.UnitySDKManager.<PostData>d__25::MoveNext
0x00b12be4 │ │ ┌─UnitySDK.UnitySDKManager::GetUrl
0x00b12be4 │ │ └─UnitySDK.UnitySDKManager::GetUrl
0x0247db9c │ │ ┌─UnityEngine.Networking.UnityWebRequest::.ctor
0x0247db00 │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::set_url
0x0247ef38 │ │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::InternalSetUrl
0x0247ef38 │ │ │ │ └─UnityEngine.Networking.UnityWebRequest::InternalSetUrl
0x0247db00 │ │ │ └─UnityEngine.Networking.UnityWebRequest::set_url
0x0247dc1c │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::set_method
0x0247e4e0 │ │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::InternalSetMethod
0x0247e4e0 │ │ │ │ └─UnityEngine.Networking.UnityWebRequest::InternalSetMethod
0x0247dc1c │ │ │ └─UnityEngine.Networking.UnityWebRequest::set_method
0x0247db9c │ │ └─UnityEngine.Networking.UnityWebRequest::.ctor
0x0247e0f4 │ │ ┌─UnityEngine.Networking.UnityWebRequest::set_uploadHandler
0x0247e0f4 │ │ └─UnityEngine.Networking.UnityWebRequest::set_uploadHandler
0x0247dfdc │ │ ┌─UnityEngine.Networking.UnityWebRequest::set_downloadHandler
0x0247dfdc │ │ └─UnityEngine.Networking.UnityWebRequest::set_downloadHandler
0x0247f66c │ │ ┌─UnityEngine.Networking.UnityWebRequest::SetRequestHeader
0x0247f66c │ │ └─UnityEngine.Networking.UnityWebRequest::SetRequestHeader
0x0247e42c │ │ ┌─UnityEngine.Networking.UnityWebRequest::Send
0x0247e430 │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::SendWebRequest
0x0247e42c │ │ │ └─UnityEngine.Networking.UnityWebRequest::Send
0x0247e430 │ │ └─UnityEngine.Networking.UnityWebRequest::SendWebRequest
0x00a3422c │ └─UnitySDK.UnitySDKManager.<PostData>d__25::MoveNext
0x00a34cd4 │ ┌─UnitySDK.UnitySDKManager.<PostData>d__25::System.Collections.IEnumerator.get_Current
0x00a34cd4 │ └─UnitySDK.UnitySDKManager.<PostData>d__25::System.Collections.IEnumerator.get_Current
0x00b15b44 └─UnitySDK.UnitySDKManager::ServerVerifyApk
0x00b15b44 ┌─UnitySDK.UnitySDKManager::ServerVerifyApk
0x00b04b3c │ ┌─UnitySDK.UnitySDKManager::GetFileInfoList
0x00b04b3c │ └─UnitySDK.UnitySDKManager::GetFileInfoList
0x00b06ec0 │ ┌─UnitySDK.UnitySDKManager::GetGamePackageName
0x00b06ec0 │ └─UnitySDK.UnitySDKManager::GetGamePackageName
0x00b06204 │ ┌─UnitySDK.UnitySDKManager::GetSDKVersion
0x00b06204 │ └─UnitySDK.UnitySDKManager::GetSDKVersion
0x00b06278 │ ┌─UnitySDK.UnitySDKManager::HexStringToHex
0x00b06278 │ └─UnitySDK.UnitySDKManager::HexStringToHex
0x00b10fcc │ ┌─UnitySDK.UnitySDKManager::EncryptString
0x00b10fcc │ └─UnitySDK.UnitySDKManager::EncryptString
0x00b100a4 │ ┌─UnitySDK.UnitySDKManager::PostData
0x00a341fc │ │ ┌─UnitySDK.UnitySDKManager.<PostData>d__25::.ctor
0x00a341fc │ │ └─UnitySDK.UnitySDKManager.<PostData>d__25::.ctor
0x00b100a4 │ └─UnitySDK.UnitySDKManager::PostData
0x00a3422c │ ┌─UnitySDK.UnitySDKManager.<PostData>d__25::MoveNext
0x00b12be4 │ │ ┌─UnitySDK.UnitySDKManager::GetUrl
0x00b12be4 │ │ └─UnitySDK.UnitySDKManager::GetUrl
0x0247db9c │ │ ┌─UnityEngine.Networking.UnityWebRequest::.ctor
0x0247db00 │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::set_url
0x0247ef38 │ │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::InternalSetUrl
0x0247ef38 │ │ │ │ └─UnityEngine.Networking.UnityWebRequest::InternalSetUrl
0x0247db00 │ │ │ └─UnityEngine.Networking.UnityWebRequest::set_url
0x0247dc1c │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::set_method
0x0247e4e0 │ │ │ │ ┌─UnityEngine.Networking.UnityWebRequest::InternalSetMethod
0x0247e4e0 │ │ │ │ └─UnityEngine.Networking.UnityWebRequest::InternalSetMethod
0x0247dc1c │ │ │ └─UnityEngine.Networking.UnityWebRequest::set_method
0x0247db9c │ │ └─UnityEngine.Networking.UnityWebRequest::.ctor
0x0247e0f4 │ │ ┌─UnityEngine.Networking.UnityWebRequest::set_uploadHandler
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最后于 2023-11-2 23:33
被wx_嗨编辑
,原因: 编辑标题