对于绕过ssl pinning的产品有很多,其中最著名的当属JustTrustMe。其他的sslUnPinning产品思想很多都是从JustTrustMe那里抄来的,由于JustTrustMe原作者也不更新了但是反sslUnPinning技术一直在前进,所以我决定用1一个月的业余时间来重新打造一款实用的sslUnPinning产品。
JustTrustMe我是很认可他的插桩点位的思路的。但是,本人是不认可xposed的。xposed的hook机制从设计之初就走了一条“不归路”,因为xposed有太多的特征可以被app检测。主要是xposed必须基于替换受精卵进程来实现,并且还要安装对应的app来管理插件,而且插件开发也要是单独的android工程。这个对于被攻击app来讲非常好从多个维度去检测xposed的存在,只是人家不想搞的这么明显大多不会强制退出app罢了。比如微信大家去jadx搜索代码,里面妥妥去检测了xposed,人家早就把你标记了。有些小team拿着官方已经停止更新的xposed改改包名,然后称之为魔改过反检测。其实,我要检测你,你怎么改都反不了。你包名改掉,但是你自定义的包名依然在调用栈里面。通过对比纯净android系统的正常堆栈,你立马被标记为灰度用户。还可以通过扫描已经安装的app列表,发现类似justtrustme之类的应用立马标记。还有你xposed管理本身也是一个app,你怎么隐藏? 改操作系统吗?但是,话又回来了,你都可以改操作系统了那你为什么不直接在framework层直接嵌入hook机制呢?因为,你技术还没到那一步,你只是停留在andorid项目改改包名的阶段,只能靠着这个去收割一些新人的韭菜。不好意思阿,我这人说话就是这么直!你费劲巴拉的搞一个大型项目,完了效果并不是真的全面反检测。我觉得没必要去做。
我想xposed的作者rovo89也是看到了这一点,所以没有再对xposed进行更新了。大庄家都不玩了,我们这些蝼蚁就要认清局势。该废弃的技术废弃,要舍得抛弃陈旧的技术这样你才能不断进步。我要把JustTrustMe用frida实现一版。所以先出一篇JustTrustMe源码分析,等大家熟悉了JustTrustMe源码我再带着大家用frida去搞一个"JustTrustMe":
请大家先打开JustTrustMe的Main.java,我下面会一一列举JustTrustMe的每个方法,以及它的作用和对应java的伪代码。
分析:三个构造方法的目的都是在new DefaultHttpClient之后替换connManager参数。而getSCCM()方法就是返回一个不安全的ClientConnectionManager。
getSCCM()和getCCM()实现如下:
那么,由此我们得到经过hook之后三个方法的伪代码逻辑。
分析:X509TrustManagerExtensions原方法会进行一系列的效应证书和服务器是否可信。这里xposed用了XC_MethodReplacement直接替换方法的执行体。
那么,伪代码逻辑如下:
分析:原NetworkSecurityTrustManager类的checkPins方法List参数原型是List<X509Certificate>。校验X509Certificate集合是否合法,如果不合法就会抛CertificateException。这里xposed用了XC_MethodReplacement直接替换方法的执行体,并且什么都没做。
那么,伪代码逻辑如下:
分析:这个稍微有点复杂,但目的很简单。就是为了替换TrustManager,而TrustManager不可以直接传进来,是内部创建一个sslcontext来包装一个TrustManager[]。所以要new一个自定义的sslcontext然后把ImSureItsLegitTrustManager传进去。sslcontext对象要进行init()所以整个代码看起来比较多。
给你看伪代码,那逻辑将一目了然:
分析:很好理解
伪代码:
分析:强制让isSecure返回true
伪代码:
分析:如果存在com.android.org.conscrypt.TrustManagerImpl这个类的,并且返回的TrustManager[]的长度大于0,并且TrustManager[]第0个是com.android.org.conscrypt.TrustManagerImpl实例,则什么都不操作。否则直接把返回值改成TrustManager[]{new ImSureItsLegitTrustManager()}
伪代码:
分析:让setDefaultHostnameVerifier方法失效,让setSSLSocketFactory失效,让setHostnameVerifier失效
伪代码:
分析:不用第0和低2个参数,而第1个参数使用TrustManager[]{new ImSureItsLegitTrustManager()}
伪代码:
分析:由于xposed基于zygote进程孵化app进程,hook非常早。所以如果它想对应用层的类进行hook的话,必须等Application的attach调用之后才能拿到应用级的ClassLoader。那么在attach之后他又进行了processOkHttp、processHttpClientAndroidLib、processXutils方法的调用,分别对应okhttp库的hook、httpclientandroidlib库的hook、org.xutils.http的hook。这三个是应用喜欢用的三方http库。
伪代码:
分析okhttp包名不统一问题:由于okhttp 2.x和3.x包名相差比较大。所以这里第一个hook你可以看到justTrustMe试图去找com.squareup.okhttp.CertificatePinner类,这是为了尽量兼容老安卓项目。
分析CertificatePinner.check:无论是okhttp2.x还是3.x、4.x都是有CertificatePinner.check(String str, List<Certificate> list)这个方法的。可以上面第一二个hook做的是XC_MethodReplacement,并且什么都不操作。对比原check方法,我们知道这个目的是为了阻止check抛SSLPeerUnverifiedException异常。
CertificatePinner.check伪代码:
分析:第三四个hook OkHostnameVerifier.verify(),校验hostname是否合法最终会调用verify(str, (X509Certificate) sSLSession.getPeerCertificates()[0]);说明还是对远程服务证书进行了校验,这里直接用return true替代了原来的逻辑。
分析:一个冷门http库的hook
伪代码:
分析:一个冷门http库的hook
伪代码:
到目前为止,我们已经把JustTrustMe所有的hook点位全部分析了一遍。中间如果大家还是有不解的地方可以去查看每个类对应的源码,下列我帮大家找了一些
JustTrustMe Main.java
apache http DefaultHttpClient.java
android framework X509TrustManagerExtensions.java
android framework NetworkSecurityTrustManager.java
apache http SSLSocketFactory.java
javax TrustManagerFactory.java
javax HttpsURLConnection.java
javax SSLContext.java
android framework TrustManagerImpl.java
okhttp3 CertificatePinner.java
okhttp3 OkHostnameVerifier.java
/
*
external
/
apache
-
http
/
src
/
org
/
apache
/
http
/
impl
/
client
/
DefaultHttpClient.java
*
/
/
*
public DefaultHttpClient()
*
/
findAndHookConstructor(DefaultHttpClient.
class
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
setObjectField(param.thisObject,
"defaultParams"
, null);
setObjectField(param.thisObject,
"connManager"
, getSCCM());
}
});
/
*
external
/
apache
-
http
/
src
/
org
/
apache
/
http
/
impl
/
client
/
DefaultHttpClient.java
*
/
/
*
public DefaultHttpClient(HttpParams params)
*
/
findAndHookConstructor(DefaultHttpClient.
class
, HttpParams.
class
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
setObjectField(param.thisObject,
"defaultParams"
, (HttpParams) param.args[
0
]);
setObjectField(param.thisObject,
"connManager"
, getSCCM());
}
});
/
*
external
/
apache
-
http
/
src
/
org
/
apache
/
http
/
impl
/
client
/
DefaultHttpClient.java
*
/
/
*
public DefaultHttpClient(ClientConnectionManager conman, HttpParams params)
*
/
findAndHookConstructor(DefaultHttpClient.
class
, ClientConnectionManager.
class
, HttpParams.
class
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
HttpParams params
=
(HttpParams) param.args[
1
];
setObjectField(param.thisObject,
"defaultParams"
, params);
setObjectField(param.thisObject,
"connManager"
, getCCM(param.args[
0
], params));
}
});
/
*
external
/
apache
-
http
/
src
/
org
/
apache
/
http
/
impl
/
client
/
DefaultHttpClient.java
*
/
/
*
public DefaultHttpClient()
*
/
findAndHookConstructor(DefaultHttpClient.
class
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
setObjectField(param.thisObject,
"defaultParams"
, null);
setObjectField(param.thisObject,
"connManager"
, getSCCM());
}
});
/
*
external
/
apache
-
http
/
src
/
org
/
apache
/
http
/
impl
/
client
/
DefaultHttpClient.java
*
/
/
*
public DefaultHttpClient(HttpParams params)
*
/
findAndHookConstructor(DefaultHttpClient.
class
, HttpParams.
class
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
setObjectField(param.thisObject,
"defaultParams"
, (HttpParams) param.args[
0
]);
setObjectField(param.thisObject,
"connManager"
, getSCCM());
}
});
/
*
external
/
apache
-
http
/
src
/
org
/
apache
/
http
/
impl
/
client
/
DefaultHttpClient.java
*
/
/
*
public DefaultHttpClient(ClientConnectionManager conman, HttpParams params)
*
/
findAndHookConstructor(DefaultHttpClient.
class
, ClientConnectionManager.
class
, HttpParams.
class
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
HttpParams params
=
(HttpParams) param.args[
1
];
setObjectField(param.thisObject,
"defaultParams"
, params);
setObjectField(param.thisObject,
"connManager"
, getCCM(param.args[
0
], params));
}
});
/
/
Create a SingleClientConnManager that trusts everyone!
public ClientConnectionManager getSCCM() {
KeyStore trustStore;
try
{
trustStore
=
KeyStore.getInstance(KeyStore.getDefaultType());
trustStore.load(null, null);
SSLSocketFactory sf
=
new TrustAllSSLSocketFactory(trustStore);
sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
SchemeRegistry registry
=
new SchemeRegistry();
registry.register(new Scheme(
"http"
, PlainSocketFactory.getSocketFactory(),
80
));
registry.register(new Scheme(
"https"
, sf,
443
));
ClientConnectionManager ccm
=
new SingleClientConnManager(null, registry);
return
ccm;
} catch (Exception e) {
return
null;
}
}
/
/
This function creates a ThreadSafeClientConnManager that trusts everyone!
public ClientConnectionManager getTSCCM(HttpParams params) {
KeyStore trustStore;
try
{
trustStore
=
KeyStore.getInstance(KeyStore.getDefaultType());
trustStore.load(null, null);
SSLSocketFactory sf
=
new TrustAllSSLSocketFactory(trustStore);
sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
SchemeRegistry registry
=
new SchemeRegistry();
registry.register(new Scheme(
"http"
, PlainSocketFactory.getSocketFactory(),
80
));
registry.register(new Scheme(
"https"
, sf,
443
));
ClientConnectionManager ccm
=
new ThreadSafeClientConnManager(params, registry);
return
ccm;
} catch (Exception e) {
return
null;
}
}
/
/
This function determines what
object
we are dealing with.
public ClientConnectionManager getCCM(
Object
o, HttpParams params) {
String className
=
o.getClass().getSimpleName();
if
(className.equals(
"SingleClientConnManager"
)) {
return
getSCCM();
}
else
if
(className.equals(
"ThreadSafeClientConnManager"
)) {
return
getTSCCM(params);
}
return
null;
}
/
/
Create a SingleClientConnManager that trusts everyone!
public ClientConnectionManager getSCCM() {
KeyStore trustStore;
try
{
trustStore
=
KeyStore.getInstance(KeyStore.getDefaultType());
trustStore.load(null, null);
SSLSocketFactory sf
=
new TrustAllSSLSocketFactory(trustStore);
sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
SchemeRegistry registry
=
new SchemeRegistry();
registry.register(new Scheme(
"http"
, PlainSocketFactory.getSocketFactory(),
80
));
registry.register(new Scheme(
"https"
, sf,
443
));
ClientConnectionManager ccm
=
new SingleClientConnManager(null, registry);
return
ccm;
} catch (Exception e) {
return
null;
}
}
/
/
This function creates a ThreadSafeClientConnManager that trusts everyone!
public ClientConnectionManager getTSCCM(HttpParams params) {
KeyStore trustStore;
try
{
trustStore
=
KeyStore.getInstance(KeyStore.getDefaultType());
trustStore.load(null, null);
SSLSocketFactory sf
=
new TrustAllSSLSocketFactory(trustStore);
sf.setHostnameVerifier(SSLSocketFactory.ALLOW_ALL_HOSTNAME_VERIFIER);
SchemeRegistry registry
=
new SchemeRegistry();
registry.register(new Scheme(
"http"
, PlainSocketFactory.getSocketFactory(),
80
));
registry.register(new Scheme(
"https"
, sf,
443
));
ClientConnectionManager ccm
=
new ThreadSafeClientConnManager(params, registry);
return
ccm;
} catch (Exception e) {
return
null;
}
}
/
/
This function determines what
object
we are dealing with.
public ClientConnectionManager getCCM(
Object
o, HttpParams params) {
String className
=
o.getClass().getSimpleName();
if
(className.equals(
"SingleClientConnManager"
)) {
return
getSCCM();
}
else
if
(className.equals(
"ThreadSafeClientConnManager"
)) {
return
getTSCCM(params);
}
return
null;
}
public DefaultHttpClient(final ClientConnectionManager conman, final HttpParams params) {
super
(getCCM(conman, params), params);
}
public DefaultHttpClient(final HttpParams params) {
super
(getSCCM(), params);
}
public DefaultHttpClient() {
super
(getSCCM(), null);
}
public DefaultHttpClient(final ClientConnectionManager conman, final HttpParams params) {
super
(getCCM(conman, params), params);
}
public DefaultHttpClient(final HttpParams params) {
super
(getSCCM(), params);
}
public DefaultHttpClient() {
super
(getSCCM(), null);
}
findAndHookMethod(X509TrustManagerExtensions.
class
,
"checkServerTrusted"
, X509Certificate[].
class
, String.
class
, String.
class
, new XC_MethodReplacement() {
@Override
protected
Object
replaceHookedMethod(MethodHookParam param) throws Throwable {
return
param.args[
0
];
}
});
findAndHookMethod(X509TrustManagerExtensions.
class
,
"checkServerTrusted"
, X509Certificate[].
class
, String.
class
, String.
class
, new XC_MethodReplacement() {
@Override
protected
Object
replaceHookedMethod(MethodHookParam param) throws Throwable {
return
param.args[
0
];
}
});
public
List
<X509Certificate> checkServerTrusted(X509Certificate[] chain, String authType, String host) throws CertificateException {
return
chain;
}
public
List
<X509Certificate> checkServerTrusted(X509Certificate[] chain, String authType, String host) throws CertificateException {
return
chain;
}
findAndHookMethod(
"android.security.net.config.NetworkSecurityTrustManager"
, lpparam.classLoader,
"checkPins"
,
List
.
class
, new XC_MethodReplacement() {
@Override
protected
Object
replaceHookedMethod(MethodHookParam param) throws Throwable {
return
null;
}
});
findAndHookMethod(
"android.security.net.config.NetworkSecurityTrustManager"
, lpparam.classLoader,
"checkPins"
,
List
.
class
, new XC_MethodReplacement() {
@Override
protected
Object
replaceHookedMethod(MethodHookParam param) throws Throwable {
return
null;
}
});
private void checkPins(
List
<X509Certificate> chain) throws CertificateException {
}
private void checkPins(
List
<X509Certificate> chain) throws CertificateException {
}
/
*
external
/
apache
-
http
/
src
/
org
/
apache
/
http
/
conn
/
ssl
/
SSLSocketFactory.java
*
/
/
*
public SSLSocketFactory( ... )
*
/
findAndHookConstructor(SSLSocketFactory.
class
, String.
class
, KeyStore.
class
, String.
class
, KeyStore.
class
,
SecureRandom.
class
, HostNameResolver.
class
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
String algorithm
=
(String) param.args[
0
];
KeyStore keystore
=
(KeyStore) param.args[
1
];
String keystorePassword
=
(String) param.args[
2
];
SecureRandom random
=
(SecureRandom) param.args[
4
];
KeyManager[] keymanagers
=
null;
TrustManager[] trustmanagers
=
null;
if
(keystore !
=
null) {
keymanagers
=
(KeyManager[]) callStaticMethod(SSLSocketFactory.
class
,
"createKeyManagers"
, keystore, keystorePassword);
}
trustmanagers
=
new TrustManager[]{new ImSureItsLegitTrustManager()};
setObjectField(param.thisObject,
"sslcontext"
, SSLContext.getInstance(algorithm));
callMethod(getObjectField(param.thisObject,
"sslcontext"
),
"init"
, keymanagers, trustmanagers, random);
setObjectField(param.thisObject,
"socketfactory"
,
callMethod(getObjectField(param.thisObject,
"sslcontext"
),
"getSocketFactory"
));
}
});
/
*
external
/
apache
-
http
/
src
/
org
/
apache
/
http
/
conn
/
ssl
/
SSLSocketFactory.java
*
/
/
*
public SSLSocketFactory( ... )
*
/
findAndHookConstructor(SSLSocketFactory.
class
, String.
class
, KeyStore.
class
, String.
class
, KeyStore.
class
,
SecureRandom.
class
, HostNameResolver.
class
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
String algorithm
=
(String) param.args[
0
];
KeyStore keystore
=
(KeyStore) param.args[
1
];
String keystorePassword
=
(String) param.args[
2
];
SecureRandom random
=
(SecureRandom) param.args[
4
];
KeyManager[] keymanagers
=
null;
TrustManager[] trustmanagers
=
null;
if
(keystore !
=
null) {
keymanagers
=
(KeyManager[]) callStaticMethod(SSLSocketFactory.
class
,
"createKeyManagers"
, keystore, keystorePassword);
}
trustmanagers
=
new TrustManager[]{new ImSureItsLegitTrustManager()};
setObjectField(param.thisObject,
"sslcontext"
, SSLContext.getInstance(algorithm));
callMethod(getObjectField(param.thisObject,
"sslcontext"
),
"init"
, keymanagers, trustmanagers, random);
setObjectField(param.thisObject,
"socketfactory"
,
callMethod(getObjectField(param.thisObject,
"sslcontext"
),
"getSocketFactory"
));
}
});
public SSLSocketFactory(
String algorithm,
final KeyStore keystore,
final String keystorePassword,
final KeyStore truststore,
final SecureRandom random,
final HostNameResolver nameResolver)
throws NoSuchAlgorithmException, KeyManagementException, KeyStoreException, UnrecoverableKeyException
{
super
();
if
(algorithm
=
=
null) {
algorithm
=
TLS;
}
KeyManager[] keymanagers
=
null;
if
(keystore !
=
null) {
keymanagers
=
createKeyManagers(keystore, keystorePassword);
}
TrustManager[] trustmanagers
=
new TrustManager[]{new ImSureItsLegitTrustManager()};;
/
/
这里被替换了,就这么简单
this.sslcontext
=
SSLContext.getInstance(algorithm);
this.sslcontext.init(keymanagers, trustmanagers, random);
this.socketfactory
=
this.sslcontext.getSocketFactory();
this.nameResolver
=
nameResolver;
}
public SSLSocketFactory(
String algorithm,
final KeyStore keystore,
final String keystorePassword,
final KeyStore truststore,
final SecureRandom random,
final HostNameResolver nameResolver)
throws NoSuchAlgorithmException, KeyManagementException, KeyStoreException, UnrecoverableKeyException
{
super
();
if
(algorithm
=
=
null) {
algorithm
=
TLS;
}
KeyManager[] keymanagers
=
null;
if
(keystore !
=
null) {
keymanagers
=
createKeyManagers(keystore, keystorePassword);
}
TrustManager[] trustmanagers
=
new TrustManager[]{new ImSureItsLegitTrustManager()};;
/
/
这里被替换了,就这么简单
this.sslcontext
=
SSLContext.getInstance(algorithm);
this.sslcontext.init(keymanagers, trustmanagers, random);
this.socketfactory
=
this.sslcontext.getSocketFactory();
this.nameResolver
=
nameResolver;
}
findAndHookMethod(
"org.apache.http.conn.ssl.SSLSocketFactory"
, lpparam.classLoader,
"getSocketFactory"
, new XC_MethodReplacement() {
@Override
protected
Object
replaceHookedMethod(MethodHookParam param) throws Throwable {
return
(SSLSocketFactory) newInstance(SSLSocketFactory.
class
);
}
});
findAndHookMethod(
"org.apache.http.conn.ssl.SSLSocketFactory"
, lpparam.classLoader,
"getSocketFactory"
, new XC_MethodReplacement() {
@Override
protected
Object
replaceHookedMethod(MethodHookParam param) throws Throwable {
return
(SSLSocketFactory) newInstance(SSLSocketFactory.
class
);
}
});
public static SSLSocketFactory getSocketFactory() {
/
/
return
NoPreloadHolder.DEFAULT_FACTORY;
return
new SSLSocketFactory();
}
public static SSLSocketFactory getSocketFactory() {
/
/
return
NoPreloadHolder.DEFAULT_FACTORY;
return
new SSLSocketFactory();
}
findAndHookMethod(
"org.apache.http.conn.ssl.SSLSocketFactory"
, lpparam.classLoader,
"isSecure"
, Socket.
class
, new XC_MethodReplacement() {
@Override
protected
Object
replaceHookedMethod(MethodHookParam param) throws Throwable {
return
true;
}
});
findAndHookMethod(
"org.apache.http.conn.ssl.SSLSocketFactory"
, lpparam.classLoader,
"isSecure"
, Socket.
class
, new XC_MethodReplacement() {
@Override
protected
Object
replaceHookedMethod(MethodHookParam param) throws Throwable {
return
true;
}
});
public boolean isSecure(Socket sock)
throws IllegalArgumentException {
return
true;
}
public boolean isSecure(Socket sock)
throws IllegalArgumentException {
return
true;
}
findAndHookMethod(
"javax.net.ssl.TrustManagerFactory"
, lpparam.classLoader,
"getTrustManagers"
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
if
(hasTrustManagerImpl()) {
Class<?>
cls
=
findClass(
"com.android.org.conscrypt.TrustManagerImpl"
, lpparam.classLoader);
TrustManager[] managers
=
(TrustManager[]) param.getResult();
if
(managers.length >
0
&&
cls
.
isInstance
(managers[
0
]))
return
;
}
param.setResult(new TrustManager[]{new ImSureItsLegitTrustManager()});
}
});
findAndHookMethod(
"javax.net.ssl.TrustManagerFactory"
, lpparam.classLoader,
"getTrustManagers"
, new XC_MethodHook() {
@Override
protected void afterHookedMethod(MethodHookParam param) throws Throwable {
if
(hasTrustManagerImpl()) {
Class<?>
cls
=
findClass(
"com.android.org.conscrypt.TrustManagerImpl"
, lpparam.classLoader);
TrustManager[] managers
=
(TrustManager[]) param.getResult();
if
(managers.length >
0
&&
cls
.
isInstance
(managers[
0
]))
return
;
}
param.setResult(new TrustManager[]{new ImSureItsLegitTrustManager()});
}
});
public final TrustManager[] getTrustManagers() {
TrustManager[] originResult
=
factorySpi.engineGetTrustManagers();
/
/
原代码是直接
return
factorySpi.engineGetTrustManagers()
if
(hasTrustManagerImpl()) {
Class<?>
cls
=
Class.
from
(
"com.android.org.conscrypt.TrustManagerImpl"
);
if
(originResult.length >
0
&&
cls
.
isInstance
(originResult[
0
])) {
return
originResult;
}
}
return
new TrustManager[]{new ImSureItsLegitTrustManager()};
}
public final TrustManager[] getTrustManagers() {
TrustManager[] originResult
=
factorySpi.engineGetTrustManagers();
/
/
原代码是直接
return
factorySpi.engineGetTrustManagers()
if
(hasTrustManagerImpl()) {
Class<?>
cls
=
Class.
from
(
"com.android.org.conscrypt.TrustManagerImpl"
);
[培训]内核驱动高级班,冲击BAT一流互联网大厂工作,每周日13:00-18:00直播授课
最后于 2021-5-6 10:34
被爬虫不看学历编辑
,原因: