Android 2.3 代碼混淆proguard技術介紹

由於各種反編譯工具的泛濫，作為Android程式員在2.3版本以前只能通過手動添加proguard來實現代碼混淆

 

proguard這個工具是一個java代碼混淆的工具

 

在2.3版本的sdk中 我們可以看到在android-sdk-windows/tools/下面多了一個proguard檔案夾

google已經把proguard技術放在了android sdk裡面 可以通過正常的編譯方式也能實現代碼混淆了

 

可以看見建立一個工程裡面有default.properties和proguard.cfg

 

預設的default.properties代碼如下

# This file is automatically generated by Android Tools.<br /># Do not modify this file -- YOUR CHANGES WILL BE ERASED!<br />#<br /># This file must be checked in Version Control Systems.<br />#<br /># To customize properties used by the Ant build system use,<br /># "build.properties", and override values to adapt the script to your<br /># project structure.<br /># Project target.<br />target=android-9<br /> 

我們可以看到proguard.cfg已經幫我們寫好了最佳化代碼指令碼

-optimizationpasses 5<br />-dontusemixedcaseclassnames<br />-dontskipnonpubliclibraryclasses<br />-dontpreverify<br />-verbose<br />-optimizations !code/simplification/arithmetic,!field/*,!class/merging/*<br />-keep public class * extends android.app.Activity<br />-keep public class * extends android.app.Application<br />-keep public class * extends android.app.Service<br />-keep public class * extends android.content.BroadcastReceiver<br />-keep public class * extends android.content.ContentProvider<br />-keep public class com.android.vending.licensing.ILicensingService<br />-keepclasseswithmembernames class * {<br /> native <methods>;<br />}<br />-keepclasseswithmembernames class * {<br /> public <init>(android.content.Context, android.util.AttributeSet);<br />}<br />-keepclasseswithmembernames class * {<br /> public <init>(android.content.Context, android.util.AttributeSet, int);<br />}<br />-keepclassmembers enum * {<br /> public static **[] values();<br /> public static ** valueOf(java.lang.String);<br />}<br />-keep class * implements android.os.Parcelable {<br /> public static final android.os.Parcelable$Creator *;<br />}<br /> 

從指令碼中可以看到，混淆中保留了繼承自Activity、Service、Application、BroadcastReceiver、ContentProvider等基本組件以及com.android.vending.licensing.ILicensingService

 

並保留了所有的Native變數名及類名，所有類中部分以設定了固定參數格式的建構函式，枚舉等等。(詳細資料請參考<proguard_path>/examples中的例子及注釋。)

 

接下來 按照google協助文檔裡說的

To enable ProGuard so that it runs as part of an Ant or Eclipse build, set the proguard.config property in the <project_root>/default.properties file. The path can be an absolute path or a path relative to the project's root. 

所以我們修改default.properties file

加上一句

proguard.config=proguard.cfg

如下

# This file is automatically generated by Android Tools.<br /># Do not modify this file -- YOUR CHANGES WILL BE ERASED!<br />#<br /># This file must be checked in Version Control Systems.<br />#<br /># To customize properties used by the Ant build system use,<br /># "build.properties", and override values to adapt the script to your<br /># project structure.<br /># Project target.<br />target=android-9<br />proguard.config=proguard.cfg<br /> 

 

然後正常的編譯簽名即可

 

然後用Android Tools產生一個發布的apk即可

 

然後用反編譯工具查看dex檔案

最後匯出反編譯之後的混淆代碼如

 

 

 

是不是很輕鬆加愉快!希望各位程式員都能保護好自己的Android代碼!