The power of root on Android emulators

Transcription

1 The power of root on Android emulators Command line tooling for Android Development Gabe Martin LinuxFest Northwest :00 AM to 10:50 AM, CC 239 Welcome Describe alternative title Questions can be asked between immediately following demos

2 About Me Android Developer (2010-Present) Android Mobile developer Windows Developer Enterprise desktop software development. Primarily Windows, Primarily C++ /. NET WWU Computer Science 2001

3 Presentation topics Interacting with Android components Activities, Services, Broadcast Receivers, Content Providers Utilizing Android SDK / Emulator tools for development and testing adb, ant, am, content, run-as Identifying differences between developing on different types of devices Emulators, rooted devices, stock devices

4 Android SDK Overview Free / Open Source Multi-platform (Mac, Linux, Windows) Java based Build Tools Debug tools Platforms (Android API3 to Android API 17) Emulator API Add-ons Platform Library Overview of Android Tooling Not all platforms are supported equally Mac Best supported. Emulators are usable and connecting to Android devices "just works." Linux Some configuration required for adb access. Windows Requires cygwin for some features. Difficult to detect some devices via ADB. Build Tools: android, ant, proguard Development tools: adb, sqlite3, profilers, monkey runner Eclipse IDE (ADT) is the recommended IDE for Android development. Many other are available including NetBeans, IntelliJ?, Visual Studio SDK Download:

5 Android SDK Demo Demo: Building an Android app using the SDK and command line Run: copy../bootstrappresentations.sh. cat bootstrappresentations.sh - if no network access is available or github error use local files android avd & # start emulator ant debug install # debug and install

6 Apps - Desktop vs Android App Lifetime Desktop Apps - process bound Have an entry point method and app exits once completed Android Apps - state bound Processes can be killed at any point and restored with existing state Key difference What happens when the app or process is "killed" by user or system Android SDK links:

7 Activity From the Android SDK An Activity is an application component that provides a screen with which users can interact in order to do something, such as dial the phone, take a photo, send an , or view a map. Each activity is given a window in which to draw its user interface. Activities are "stacked" and popped off when back is pressed. The Activity backstack is preserved by the system and not tied to a process. Learn more about Activities at David Schwegler's Developing for Android's Uniqueness Android SDK links:

8 Activities and apps Activity Activity Activity Activity Content Provider Service Dalvik VM Process Android System Linux Activities are "stacked" and popped off when back is pressed. The Activity backstack is preserved by the system and not tied to a process. Learn more about Activities at David Schwegler's Developing for Android's Uniqueness Android SDK links:

9 Activity Demo Demo: Starting Activities and killing processes from the command line Demo Start 4 activities in a row. Show how you can kill the process which effectively pops the last activity off the stack. test/showallprocesses.sh test/startactivities.sh test/showallprocesses.sh test/showappprocess.sh test/killprocess.sh test/killprocess.sh test/killprocess.sh test/startactivities.sh test/forcestop.sh Native app crashes behave in a similar manner.

10 Services From the Android SDK A Service is an application component that can perform long-running operations in the background and does not provide a user interface. Examples Downloading content Playing music More on Services -

11 Services Demo Demo: Starting a service with an intent from command line Demo test/forcestop.sh test/showappprocess.sh # Verifies app processes are not running test/startupdatesessionsforced.sh # Creates a new process and starts service test/showappprocess.sh # Shows that a process was started to run the service and is still running

12 Broadcast Receivers From the Android SDK A broadcast receiver is a component that responds to system-wide broadcast announcements. Many broadcasts originate from the system for example, a broadcast announcing that the screen has turned off, the battery is low, or a picture was captured. Applications can also initiate broadcasts for example, to let other applications know that some data has been downloaded to the device and is available for them to use.

13 Broadcast Receivers Demo Demo: Sending broadcast intents from command line Demo test/startsessionsactivity.sh test/broadcastupdatestarted.sh test/broadcastupdatecompleted.sh test/broadcastupdaterefreshcontent.sh

14 Content Providers From the Android SDK: A content provider manages a shared set of application data. You can store the data in the file system, an SQLite database, on the web, or any other persistent storage location your application can access. Through the content provider, other applications can query or even modify the data (if the content provider allows it). sqlite3 is available on emulators but has limitations. Namely no command history support Demo Use content command to change the SECURE_ID used by the emulator.

15 Content Provider Demo Demo: Interacting with Content Providers from the command line showappprocess.sh simplequeryprovider.sh provider showappprocess.sh simpleinserthelloworld.sh simplequeryprovider.sh simpleinsertgoodbyeworld.sh simplequeryprovider.sh killprocess.sh showappprocess.sh querywebcontentprovider.sh provider # verify not currently running # starts process - queries empty simple content # container process started # inserts data # queries data # inserts more data # queries data # verify not currently running # starts process - queries empty simple content querywebcontentprovider.sh # Demonstrate a ContentProvider that can make web queries - dangerous. possibly allows apps to query other apps content providers for possibly sensitive or not allowed behavior

16 Android Database Fundamentals Sqlite based Default db storage location /data/data/<app>/databases/<dbname>.db Interacting with databases on emulators, easy! sqlite3 binary included in device images emulators have root access so db files are accessible Accessing databases on non-rooted devices, tricky but doable Debuggable Android apps support run-as run-as broken on Android 2.2 when more than 50 apps are installed

17 Run-as command demo Demo: Accessing private databases The run-as command is what makes it possible to debug apps on stock devices. Useful command to also access otherwise restricted data. runasshowdatabases.sh runasmakesessionsdatabasewritable.sh runaspullsessionsdatabase.sh runasmakesessionsdatabasereadonly.sh sqlite3 Sessions.db Also very useful for accessing/changing private app preferences and files

18 Monkey - because it's fun Demo: monkey test tool for fuzz testing UI Demo monkey.sh # starts the monkey.sh UI fuzz testing tool

19 The End Questions? Git Repos Google Presentation com/presentation/d/1ryctjgct6owazsu6kuenzbywdh4lyza5bw4zn10ywks /edit?usp=sharing Special Thanks David Schwegler for making an awesome LFNW 2013 app (Make sure to attend Developing for Android's Uniqueness at 1:30 same room)