從系統的角度去尋找hook點，而不是為了抓包而抓包。
public static final MediaType JSON
= MediaType.get("application/json; charset=utf-8");
OkHttpClient client = new OkHttpClient();
String post(String url, String json) throws IOException {
RequestBody body = RequestBody.create(json, JSON);
Request request = new Request.Builder()
.url(url)
.post(body)
.build();
try (Response response = client.newCall(request).execute()) {
return response.body().string();
}
}客戶端的重要程式碼在client.newCall()上，上面是okhttp官網的範例。從此處介面呼叫開始，終會呼叫至okhttp框架, okhttp本是sdk，後來aosp已經整合至系統，所以可以歸類至框架層。
框架層不詳述，主要就是這幾個java類別:
com.android.okhttp.internal.huc.HttpURLConnectionImpl com.android.okhttp.internal.http.HttpEngine com.android.okhttp.internal.http.RetryableSink com.android.okhttp.internal.http.CacheStrategy$Factory
其實client.newCall終會透過URL取得一個connection
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
這裡的urlConnection其實就是HttpURLConnectionImpl的實例，該類別有getInputStream getOutputStream方法，內部分別會呼叫HttpEngine的getBufferedRequestBody，getResponse。剛開始我嘗試hook過這兩個接口，例如hook getResponse後，可以將response印出來.
後來我發現，Request只能輸出header，無法輸出body。所以又埋頭繼續分析，getBufferedRequestBody這個函數剛好可以入手，取得一個sink，最後以RetryableSink為突破點，例如hook 其write函數就可以將body印出來。 write函數對應於app層面的urlConnection.getOutputStream().write。
後來發現一個Request,呼叫getBufferedReuqestBody函數可能不只一次，所以會有資料重複的問題，後來我又尋找到了CacheStrategy$Factory.get點進行Hook，發現還是有資料重複。發現以上hook都有弊端
資料重複
#非okhttp呼叫無法抓取
okhttp流程：sdk接口->okhttp框架->native(libc)
var Logd = function Logd(tag, msg) {
Java.use("android.util.Log").d(tag, msg);
};
Logd('http-body-', '11111111111111');//该log不打印
Logd('http-body', '11111111111111');//该log打印var printRequest = function(request) {
var Buffer = Java.use("com.android.okhttp.okio.Buffer");
var bodyField = request.getClass().getDeclaredField('body');
bodyField.setAccessible(true);
if (request == null) return;
Logd('http', 'printRequest: request' + request);
//var requestBody = request.body();//gadget直接报错
var requestBody = bodyField.get(request);
var requestBodyClass = requestBody.getClass();
var ClassInstanceArray = Java.array('java.lang.Class', []);
//var contentLengthMethod = requestBodyClass.getMethod("contentLength");//gadget直接报错
var contentLengthMethod = requestBodyClass.getMethod("contentLength", ClassInstanceArray);
contentLengthMethod.setAccessible(true);
var ObjectInstanceArray = Java.array('java.lang.Object', []);
var contentLength = requestBody ? contentLengthMethod.invoke(requestBody, ObjectInstanceArray) : 0;
//if (contentLength == 0) contentLength = contentLen;
Logd('http', 'printRequest contentLength: ' + contentLength);
if (contentLength > 0) {
var BufferObj = Buffer.$new();
requestBody.writeTo(BufferObj);
Logd(TAG, "\nrequest body :\n" + BufferObj.readString() + "\n");
}
};var printIntentAndExtras = function printIntentAndExtras(intentObj) {
if (intentObj == null) return;
var Intent = Java.use("android.content.Intent");
var Bundle = Java.use("android.os.Bundle");
var bundleObj = Intent.getExtras.call(intentObj);
if (bundleObj != null) {
Bundle.getSize.call(bundleObj, null);//调用getSize即可反序列化
}
Logd(TAG, ‘printIntentAndExtras ’ + bundleObj);
};var URLHook = function() {
var URL = Java.use('java.net.URL');
URL.openConnection.overload().implementation = function() {
var retval = this.openConnection();
Logd('URL', openConnection' + retval);
return retval;
};
};//URL.openConnection调用概率比较大，但是不一定对网络进行请求
var jsonHook = function() {
var xx = Java.use('e.h.a.a');//app smali
var xxa_method = xx.a.overload('org.json.JSONObject', 'java.lang.String', 'java.lang.String');
xxa_method.implementation = function(jsonObj, str1, str2) {
Logd("json", jsonObj + " str1: " + str1 + " str2" + str2);
xxa_method.call(this, jsonObj, str1, str2);
}
}var traceAllHttpClass = function() {
Java.perform(function() {
Java.enumerateLoadedClasses({
onMatch: function(name, handle) {
/*"e.h.a.a$a",起初也拦截过app的该混淆类*/
if (name.indexOf("com.android.okhttp.Http") != -1 || name.indexOf("com.android.okhttp.Request") != -1
|| name.indexOf("com.android.okhttp.internal") != -1) {
traceClass(name);//对这三个class进行trace
}
},
onComplete: function() {
}
});
});
};var BuilderClass = Java.use('com.android.okhttp.Request$Builder')
BuilderClass.build.implementation = function () {
//LOG('com.android.okhttp.HttpUrl$Builder.build overload', { c: Color.Light.Cyan });
//printBacktrace();
var retval = this.build();
Logd(TAG, "retval:" + retval);
printRequest(retval);
return retval;
}var nativePropertyGetAddr = Module.findExportByName(null, '__system_property_get');
Interceptor.attach(nativePropertyGetAddr, {
onEnter: function onEnter(args) {
this._name = args[0].readCString();
this._value = args[1];
},
onLeave: function onLeave(retval) {
if (this._name.indexOf("ro.build.id") != -1) {
var virtualDevice = getVirtualDevice();
if (DEBUG_PROP) Logd(TAG, "__system_property_get fake " + this._name + "=>to " + virtualDevice.build_id);
this._value.writeUtf8String(virtualDevice.build_id);
}
var strFilter = /^ro\./g;
if (DEBUG_PROP && this._name.match(strFilter) != null) Logd(TAG, "__system_property_get " + this._name);
}
});var DEBUG_PROP = false;
var DEVICE_CONFIG = "/sdcard/.device";
function getVirtualDevice() {
var nativeOpen = new NativeFunction(Module.findExportByName(‘libc.so’, 'open'), 'int', ['pointer', 'int']);
var nativeRead = new NativeFunction(Module.findExportByName('libc.so', 'read'), 'int', ['int', 'pointer', 'int']);
var fd = nativeOpen(Memory.allocUtf8String(DEVICE_CONFIG), 0);
var mem = Memory.alloc(1024);
var readLen = nativeRead(fd, mem, 1024);
var json = JSON.parse(mem.readCString(readLen));
return json;
}
Secure.getString.implementation = function () {
var retval = this.getString(arguments[0], arguments[1]);
if (DEBUG_PROP) Logd(TAG, "Settings.Secure get " + arguments[1] + " val " + retval);
if (arguments[1].indexOf("android_id") != -1) {
var virtualDevice = getVirtualDevice();
return virtualDevice.android_id;
}
return retval;
};Java.perform(function(){
const groups = Java.enumerateMethods('*!verify/u');
var classes = null;
for(var i in groups){
var classes = groups[i]['classes'];
for(var i in classes){
Java.use(classes[i]['name'])
.verify
.overload('java.lang.String', 'javax.net.ssl.SSLSession')
.implementation = function() {
printBacktrace();
LOG("[+] invoke verify", { c: Color.Red });
return true;
}
}
}
});res/xml/network_security_config.xml
HTTP/1.1 200 OK
Date: Sun, 16 Aug 2020 06:27:34 GMT
Content-Type: application/json
Content-Length: 101
Connection: keep-alive
Grpc-Metadata-Content-Type: application/grpc
Vary: Origin
Vary: Accept-Encoding
{"result":{"errno":"OK","errmsg":"成功"},"data":{"version":"xxxxxxxx-351e-40cf-aaa9-3177d6df9b7f"}}
-----------------------------------
HTTP/1.1 200 OK
Date: Sun, 16 Aug 2020 06:27:34 GMT
Content-Type: application/json
Content-Length: 99
Connection: keep-alive
Grpc-Metadata-Content-Type: application/grpc
Vary: Origin
Vary: Accept-Encoding
{"result":{"errno":"OK","errmsg":"成功"},"data":{"nodeToken":"xxxxxxxc24d79f55c0b07beaf50cb566"}}POST https://tap-xxxxxxx.xxxxxx.com/api/v2/Android/analytics/basic HTTP/1.1
Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cjbcjdsabcjvbXVCJ9.eyJ1aWQiOjE4ODMzMDEsInNlY3JldCI6IjAzNzE0M2Y3LTExMTUtNGY2Yi1iNzQxLWUyMjc5ZDM3MGY3MCIsImV4cCI6MTU5NzgxNjQ0MiwiaXNzIjoiZ3Vlc3QgbG9naW4ifQ.W3SiO0-afbhxPITjRinnhyWhZLy1bzZhYexm5VCWklI
X-Device-ID: 9xxxxxxx84d4542e
X-Loc: ["China","Shanghai","Shanghai","","ChinaUnicom","31.224349","121.4767528","Asia/Shanghai","UTC+8","310000","86","CN","AP","xxx.166.xxx.xxx"]
X-App-Version: 2.2.0
Content-Type: application/json; charset=utf-8
Content-Length: 208
Host: xx-xxxx.xxxxxx.com
Connection: Keep-Alive
Accept-Encoding: gzip
User-Agent: okhttp/4.7.2
{"deviceID":"9xxxxxxx84d4542e","model":"V1813BA","systemVersion":"9","version":"2.2.0","location":{"latitude":xx.x99x990990991,"longitude":xxx.26689769073256},"network":{"g2":0,"g3":0,"g4":4,"g5":0,"wifi":4}}
-----------------------------------
HTTP/1.1 200 OK
Date: Sun, 16 Aug 2020 06:27:35 GMT
Content-Type: application/json
Content-Length: 43
Connection: keep-alive
Grpc-Metadata-Content-Type: application/grpc
Vary: Origin
Vary: Accept-Encoding
{"result":{"errno":"OK","errmsg":"成功"}}以上是frida如何抓apk網路包的詳細內容。更多資訊請關注PHP中文網其他相關文章！
