Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
ProGuard
Search
Edward Dale
August 31, 2017
Technology
1
450
ProGuard
An introduction to how ProGuard works.
Edward Dale
August 31, 2017
Tweet
Share
More Decks by Edward Dale
See All by Edward Dale
Write your own ProGuard
scompt
1
190
Screenshot your Entire App with Screengrab and Firebase
scompt
0
400
Screenshot your Entire App
scompt
1
1.9k
Reactive In-App Billing on Android
scompt
2
270
Fitness Motion Recognition with Android Wear
scompt
1
400
Android Apps with Mortar and Flow
scompt
7
1.6k
Functional Reactive Programming in the Mobile World
scompt
2
320
Other Decks in Technology
See All in Technology
Classmethod Odyssey 登壇資料
yamahiro
0
390
「単なる OAuth 2.0 を認証に使うと、車が通れるほどのどでかいセキュリティー・ホールができる」のか検証してみた
terara
0
380
CTOから見た事業開発とプロダクト開発 / My Perspective on Business and Product Development as CTO
keisuke69
4
960
AOAI Dev Day LLMシステム開発 Tips集
hirosatogamo
15
3.7k
Git 研修 Advanced【MIXI 24新卒技術研修】
mixi_engineers
PRO
0
200
20240717_イケコパ代表Copilot_in_Teams会社でこう使ってます
ponponmikankan
2
430
Datadog Cloud SIEMを使ってAWS環境の脅威を可視化した話/lifeistech-datadog-cloud-siem
gidajun
0
480
Azure Pipelinesを使用したCICDベースラインアーキテクチャ実践
yuriemori
0
190
成長期に歩みを止めないための創業期の開発文化形成
mayah
6
420
E2Eテスト自動化プラットフォームにおけるAIの活用
shift_evolve
0
180
What is DRE? - Road to SRE NEXT@広島
chanyou0311
3
630
dxd2024-生成AIに振り回された3か月間の成功と失敗/dxd2024-link-and-motivation
lmi
2
260
Featured
See All Featured
How to Think Like a Performance Engineer
csswizardry
4
590
Ruby is Unlike a Banana
tanoku
96
10k
Agile that works and the tools we love
rasmusluckow
325
20k
Writing Fast Ruby
sferik
623
60k
Creating an realtime collaboration tool: Agile Flush - .NET Oxford
marcduiker
16
1.6k
Intergalactic Javascript Robots from Outer Space
tanoku
266
26k
Visualization
eitanlees
139
14k
The Invisible Customer
myddelton
117
13k
BBQ
matthewcrist
82
9k
Web development in the modern age
philhawksworth
203
10k
Helping Users Find Their Own Way: Creating Modern Search Experiences
danielanewman
26
2.1k
Pencils Down: Stop Designing & Start Developing
hursman
118
11k
Transcript
ProGuard Edward Dale @scompt Freeletics https://www.freeletics.com August 31, 2017 ©
Edward Dale, 2017 1
Agenda • Overview • Steps • Problems • Future ©
Edward Dale, 2017 2
Purpose ProGuard is the most popular optimizer for Java bytecode.
It makes your Java and Android applications up to 90% smaller and up to 20% faster. ProGuard also provides minimal protection against reverse engineering by obfuscating the names of classes, fields and methods. — https://www.guardsquare.com/en/proguard © Edward Dale, 2017 3
Purpose ProGuard is the most popular optimizer for Java bytecode.
It makes your Java and Android applications up to 90% smaller and up to 20% faster. ProGuard also provides minimal protection against reverse engineering by obfuscating the names of classes, fields and methods. — https://www.guardsquare.com/en/proguard © Edward Dale, 2017 4
Highlights 1 • ProGuard is a command-line tool with an
optional graphical user interface. • ProGuard is easy to configure. A few intuitive command line options or a simple configuration file is all it takes. All available options are detailed in the user manual. 1 https://www.guardsquare.com/en/proguard © Edward Dale, 2017 5
Highlights 1 (continued) • ProGuard is fast. It processes small
Android applications and entire run-time libraries in seconds. • ProGuard is the default tool in development environments like Oracle’s Wireless Toolkit, NetBeans, EclipseME, Intel’s TXE SDK and Google’s Android SDK. 1 https://www.guardsquare.com/en/proguard © Edward Dale, 2017 6
Highlights (annotated) • ProGuard is easy to configure. A few
intuitive command line options or a simple configuration file is all it takes. All available options are detailed in the user manual. • ProGuard is fast. It processes small Android applications and entire run- time libraries in seconds. © Edward Dale, 2017 7
Steps start shrink end optimize obfuscate preverify © Edward Dale,
2017 8
Shrink Step • Enabled by default • Disabled with -dontshrink
• Removes all classes, methods, resources not reachable from from an entry point (seeds) • Dynamically referenced classes/methods need to be "kept" using -keep or -keepclasseswithmembers © Edward Dale, 2017 9
Example Class Diagram LoginActivity UserManager UserApi FeedActivity FeedApi OldUserManager OldUserApi
© Edward Dale, 2017 10
After Shrinking • No seeds LoginActivity UserManager UserApi FeedActivity FeedApi
OldUserManager OldUserApi © Edward Dale, 2017 11
After Shrinking • -keep MainActivity • -keep SecondActivity LoginActivity UserManager
UserApi FeedActivity FeedApi OldUserManager OldUserApi © Edward Dale, 2017 12
After Shrinking • -keep public class * extends android.app.Activity LoginActivity
UserManager UserApi FeedActivity FeedApi OldUserManager OldUserApi © Edward Dale, 2017 13
Keep Options -keep Specifies classes and class members (fields and
methods) to be preserved as entry points to your code. -keepclassmembers Specifies class members to be preserved, if their classes are preserved as well. -keepclasseswithmembers Specifies classes and class members to be preserved, on the condition that all of the specified class members are present. © Edward Dale, 2017 14
Optimize Step • Enabled by default • Disabled with -dontoptimize
• Performs lots of different bytecode-level optimizations to the code © Edward Dale, 2017 15
Optimize Step • -optimizationpasses declares how many times to optimize/shrink
• Freeletics does 5 passes © Edward Dale, 2017 16
Optimize Step • -optimizations can be used to disable specific
optimizations • Freeletics disables optimizations that cause problems on Android • More information in $ANDROID_HOME/tools/proguard/ proguard-android-optimize.txt © Edward Dale, 2017 17
Example Optimizations 2 • Marks methods as final, whenever possible.
• Removes unused method parameters. • Propagates the values of method parameters from method invocations to the invoked methods. • Propagates the values of method return values from methods to their invocations. • Inlines short methods. • Inlines methods that are only called once. 2 https://www.guardsquare.com/en/proguard/manual/optimizations © Edward Dale, 2017 18
Obfuscate Step • Enabled by default • Disabled with -dontobfuscate
• Classes and class members receive new short random names, except for the ones listed by the various -keep options • Internal attributes that are useful for debugging are removed © Edward Dale, 2017 19
After Obfuscation LoginActivity A B FeedActivity C OldUserManager OldUserApi ©
Edward Dale, 2017 20
Preverification Step • Enabled by default • Disabled with -dontpreverify
• When loading class files, the class loader performs some sophisticated verification of the byte code. • Unnecessary on Android © Edward Dale, 2017 21
Problems © Edward Dale, 2017 22
Problem 1 Class is unintentionally removed/obfuscated Symptom: Runtime crash java.lang.NoClassDefFoundError:
Failed resolution of: Lcom/freeletics/LoginActivity; © Edward Dale, 2017 23
Problem 1 Class is unintentionally removed/obfuscated Symptom: Runtime crash java.lang.NoClassDefFoundError:
Failed resolution of: Lcom/freeletics/LoginActivity; Solution: Ensure class is kept -keep com.freeletics.LoginActivity © Edward Dale, 2017 24
Problem 2 Code references a class not available Symptom:: Build
failure Warning: rx.internal.util.unsafe.ConcurrentCircularArrayQueue: can't find referenced class sun.misc.Unsafe ... Warning: there were 47 unresolved references to classes or interfaces. © Edward Dale, 2017 25
Problem 2 Code references a class not available Symptom:: Build
failure Warning: rx.internal.util.unsafe.ConcurrentCircularArrayQueue: can't find referenced class sun.misc.Unsafe ... Warning: there were 47 unresolved references to classes or interfaces. Solution: Don't warn about classes unavailable on Android -dontwarn sun.misc.Unsafe © Edward Dale, 2017 26
Problem 3 Adding a new library breaks build Symptom: Build
failure © Edward Dale, 2017 27
Problem 3 Adding a new library breaks build Symptom: Build
failure Solution: Google Should only happen with non-Android-specific libraries. Android-specific Libraries can add a ProGuard configuration that should be used. © Edward Dale, 2017 28
The Future we are also working on R8, which is
a Proguard replacement for whole program minification and optimization3 — James Lau, Product Manager 3 https://android-developers.googleblog.com/2017/08/next-generation-dex-compiler-now-in.html © Edward Dale, 2017 29
The Future • D8 is a dexer that converts java
byte code to dex code. • R8 is a java program shrinking and minification tool that converts java byte code to optimized dex code. • R8 is a Proguard replacement for whole-program optimization, shrinking and minification. R8 uses the Proguard keep rule format for specifying the entry points for an application. © Edward Dale, 2017 30
Questions? Edward Dale @scompt Freeletics https://www.freeletics.com © Edward Dale, 2017
31
Citations • http://knowyourmeme.com/memes/yao-ming-face-bitch- please © Edward Dale, 2017 32