Lab 5: Android Development Environment

Transcription

1 Lab 5: Android Development Environment The goal is to download the kernel sources, a cross compiler, some tools for accessing an Android OS, and an emulator. A new kernel for the ARM architecture will be built from the kernel sources and ARM kernel modules will be built and loaded into the running kernel. The kernel under test will be run from an emulator before it is pushed to an android phone. The following directories will be created - a description of their contents is given. It is assumed that all these directories are beneath ~/.android os which is referred to as root. Directory modules adt-bundle-linux goldfish toolchains../.android/avd packages Description where all the modules will be compiled location of the SDK, Eclipse, platform-tools and tools where the kernel sources will reside location of the DooMLorD ARM cross compiler location of android virtual devices repository for downloaded bundles Install and set up an OS Official guide: Storage needed: approximately 30GB Host OS: 64 bits, instructions below assume Ubuntu Linux OS utilities: use apt-get install, one at a time git, gnupg, flex, bison, gperf, build-essential, zip, wget, libc6-dev, libncurses5-dev:i386, x11proto-core-dev, libx11-dev:i386, g++-multilib, libgl1-mesa-glx:i386, libgl1-mesa-dev, libreadline6-dev:i386, mingw32, python-markdown, tofrodos, libxml2-utils, xsltproc, zlib1g-dev:i386 Packages: Android SDK, emulator, Eclipse prompt> wget \ adt-bundle-linux-x zip prompt> unzip adt-bundle-linux-x zip prompt> mv adt-bundle-linux-x adt-bundle-linux Java from Oracle (may require an account) java-archive-downloads-javase html#jdk-6u45-oth-jpr choose...linux-x64.bin prompt> chmod a+x jdk-6u45-linux-x64.bin prompt> sudo./jdk-6u45-linux-x64.bin prompt> sudo mkdir /usr/java (if it s not there) prompt> sudo mv jdk /usr/java prompt> sudo update-alternatives "/usr/local/bin/java" "java" "/usr/java/jdk /bin/java" if /usr/local/bin/java -version does not give build b06: prompt> cd /etc/alternatives prompt> sudo ln -sf /usr/java/jdk /bin/java java Make subdirectory packages and put the above zip and bin files there Utility versions: Python , GNU Make , Git 1.7 or newer Extra: prompt> cd /usr/lib/i386-linux-gnu/mesa prompt> sudo ln -s libgl.so.1 libgl.so

2 Set the PATH variable make the following change to.bash profile: export PATH=".:~/.android os/adt-bundle-linux/sdk/platform-tools: ~/.android os/adt-bundle-linux/sdk/tools:$path" Then prompt> source ~/.bash profile Create a virtual device for the emulator Find a target to tie a virtual device to prompt> android list targets id: 1 or "android-19" Name: Android 4.4 Type: Platform API level: 19 Revision: 1 Skins:... ABIs : armeabi-v7a Make the virtual device, with name avd1 tied to id 1 from above The device information will be created in ~/.android/avd/avd1.avd prompt> android create avd -n avd1 -t 1 Run the emulator on the virtual device prompt> emulator -avd avd1 Check to see what is running prompt> adb devices emulator-5554 offline After a while prompt> adb devices emulator-5554 device Identify the kernel that will be downloaded prompt> adb shell root@generic:/ # cat /proc/version Linux version gd853d22 (nnk@nnk.mtv.corp.google.com) (gcc version 4.6.x-google (prerelease) (GCC) ) #1 PREEMPT Tue Jul 9 17:46:46 PDT 2013 Leave the emulator running and open another shell Download, set up the kernel sources In the new shell, get the sources using the above information prompt> mkdir ~/.android os/goldfish /goldfish prompt> git checkout -b local-goldfish-3.4 -t origin/android-goldfish-3.4 Look at the sources prompt> ls 2

3 Get a configuration file from the running emulator prompt> adb pull /proc/config.gz prompt> gunzip config.gz prompt> mv config.config In.config change #CONFIG MODULES is not set to CONFIG MODULES=y Get cross compilers Two useful ones: prompt> git clone git://github.com/doomlord/android prebuilt toolchains.git \ toolchains prompt> ls toolchains README arm-eabi-linaro-4.6.2/ arm-eabi-4.4.3/ arm-linux-androideabi-4.7/ prompt> ls toolchains/arm-linux-androideabi-4.7/bin arm-linux-androideabi-addr2line* arm-linux-androideabi-gprof*... arm-linux-androideabi-gcc* arm-linux-androideabi-size*... In Ubuntu: prompt> sudo apt-get install binutils-arm-linux-gnueabi cpp-arm-linux-gnueabi \ cpp-4.6-arm-linux-gnueabi gcc-4.6-arm-linux-gnueabi gcc-arm-linux-gnueabi \ gcc-4.6-arm-linux-gnueabi-base This one will be used like this (the other one is used in the next section): prompt> arm-linux-gnueabi-gcc func.c -static -o func Compile the kernel Use DooMLorD: /goldfish prompt> export ARCH=arm prompt> export CROSS COMPILE=~/.android os/toolchains/arm-linux-androideabi-4.7/ \ bin/arm-linux-androideabiprompt> make Note in future compiles some kernel pieces will be compiled as modules as indicated in edits to.config. In that case this should be followed up with: prompt> make modules ; make modules install Check that the compiled image is present prompt> ls arch/arm/boot zimage*... Kill the running emulator and run the emulator on the new kernel root@generic:/ # exit prompt> emulator -kernel ~/.android os/goldfish/arch/arm/boot/zimage -avd avd1 Leave the emulator running 3

4 Make, load, test, and unload a kernel module Open a new shell and create a module prompt> mkdir modules prompt> cd modules Edit tester.c to have the following content: #include <linux/module.h> int init module(void) { printk(kern INFO "tester 1: Module loaded successfully\n"); return 0; } void cleanup module(void) { printk(kern INFO "tester 1: Module unloaded successfully\n"); } MODULE LICENSE("GPL"); Edit Makefile to have the following content: obj-m := tester.o DIR=~/.android os/goldfish PWD=~/.android os/modules CROSS COMPILE=~/.android os/toolchains/arm-linux-androideabi-4.7/bin/ \ arm-linux-androideabi- FLGS=CFLAGS MODULE=-fno-pic all: <tab>make $(FLGS) -C $(DIR) M=$(PWD) ARCH=arm CROSS COMPILE=$(CROSS COMPILE) \ modules clean: <tab>make -C $(DIR) M=$(PWD) clean Compile the module prompt> make Push the module to the running emulator; load and test it prompt> adb push tester.ko /data/ prompt> adb shell root@generic:/ # insmod /data/tester.ko root@generic:/ # dmesg tester 1: module loaded successfully Unload the module root@generic:/ # rmmod tester root@generic:/ # dmesg tester 1: module unloaded successfully 4

5 Try the second cross compiler This one seems to work well with the usual user space libraries like stdio Try it on a simple file (call it hi.c): #include <stdio.h> int main(int argc, char** argv) { printf("hello world"); return 0; } prompt> arm-linux-gnueabi-gcc hi.c -static -o hi prompt> adb push hi /data/ prompt> adb shell root@generic:/ # /data/hi hello world Get busybox utilities to augment the toolbox The pre-packaged toolbox is pitiful. At the cost of about 1MB you can have a much better toolbox to work with. Get it like this: prompt> wget tar.bz2 Compile: prompt> bzip2 -d busybox tar.bz2 prompt> tar xf busybox tar prompt> cd busybox prompt> ARCH=arm prompt> CROSS COMPILE=arm-linux-gnueabiprompt> make menuconfig de-select Networking Utilities -> Support RPC services save and exit menuconfig prompt> make Push and run: prompt> adb push busybox /data/ prompt> adb shell root@generic:/ # /data/busybox (lists all commands) root@generic:/ # /data/busybox ls One way to make the commands easier to use: root@generic:/ # /data/busybox vi /data/aliases Edit the file to look like this: alias ls= /data/busybox ls alias df= /data/busybox df alias ifconfig= /data/busybox ifconfig alias chown= /data/busybox chown... Save using <esc>: then wq Source the file and run commands: root@generic:/ # source /data/aliases root@generic:/ # ifconfig 5

6 Build an Android project in Eclipse Launch Eclipse prompt> ~/.android os/adt-bundle-linux/eclipse/eclipse Set up a (default hello world) project New -> Project -> Android Application Project Move the mouse over the Application Name field for important information Enter an application name, say First Note the warning about com, move the mouse over Package Name for important info Change com.example.first to silly.app.first Click on Next, click three more times on Next Click on Finish Explore the result Look at First -> src -> silly.app.first -> MainActivity.java Look at First -> src -> res -> layout -> activity main.xml Export the signed app as a.apk file (see key making instructions on the next page) Right click on First in the navigation side panel Choose Export Select Android -> Export Android Application Click on Next Enter First for project name Click on Next Select Use existing keystore, enter the location (e.g. /home/franco/.keystore) Enter the password for the keystore, click on Next Enter the password for the key to use, click on Next Fill in the destination.apk file (e.g. /home/franco/first.apk), click on Finish Install the app prompt> adb install ~/First.apk Find the app and run it 6

7 Make a key and certificate Make a key prompt> keytool -genkeypair -keystore ~/.keystore -keyalg "RSA" \ -keysize alias franco Enter keystore password: <password> Re-enter new password: <password> What is your first and last name? [Unknown]: John F What is the name of your organizational unit? [Unknown]: EECS What is the name of your organization? [Unknown]: U. Cinci What is the name of your City or Locality? [Unknown]: Cinci What is the name of your State or Province? [Unknown]: Ohio What is the two-letter country code for this unit? [Unknown]: US Is CN=John F, OU=EECS, O=U. Cinci, L=Cinci, ST=Ohio, C=US correct? [no]: yes Enter key password for <franco> (RETURN if same as keystore password): <return> Make a certificate prompt> keytool -selfcert -keystore ~/.keystore -alias franco Enter keystore password: <password> See what you did prompt> keytool -list -keystore ~/.keystore Enter keystore password: <password> Keystore type: JKS Keystore provider: SUN Your keystore contains 1 entry franco, Mar 23, 2014, PrivateKeyEntry, Certificate fingerprint (SHA1): 4D:A6:71:ED:A9:C1:AA:D1:73:52:AA:7A:4C:... Export the certificate prompt> keytool -exportcert -keystore ~/.keystore -alias franco -file franco.cer Enter keystore password: <password> Certificate stored in file <franco.cer> Print the certificate prompt> keytool -printcert -file franco.cer 7

8 Get and use the apktool and aapt tools Download and install the package (decompiler and apk manager) prompt> wget prompt> tar -jxf apktool1.5.2.tar.bz2 prompt> wget \ apktool-install-linux-r05-ibot.tar.bz2 prompt> tar -jxf apktool-install-linux-r05-ibot.tar.bz2 prompt> mv apktool-install-linux-r05-ibot apktool prompt> mv apktool1.5.2/* apktool/ prompt> rmdir apktool1.5.2 Edit the PATH value in ~/.bash profile and source it export PATH="~/.android os/apktool:$path" prompt> source ~/.bash profile Get a large apk file from a running emulator prompt> mkdir apk prompt> cd apk prompt> adb pull /system/app/browser.apk Decompile the file prompt> apktool decode Browser.apk Look at some files prompt> cd Browser prompt> ls prompt> more AndroidManifest.xml prompt> ls res prompt> ls smali/com/google/common/base Use aapt to examime the apk file prompt> cd.. prompt> aapt l Browser.apk prompt> aapt d badging Browser.apk prompt> aapt d permissions Browser.apk prompt> aapt d xmltree Browser.apk AndroidManifest.xml 8

9 Get and use dex2jar and jd-gui tools Download and try dex2jar (decompiles apk or dex to a jar file) prompt> cd /.android os prompt> wget prompt> unzip dex2jar zip prompt> cd dex2jar prompt> d2j-dex2jar.sh ~/First.apk dex2jar /home/franco/first.apk -> First-dex2jar.jar prompt> jar tf First-dex2jar.jar Download and try jd-gui on First-dex2jar.jar (view class files as java source) prompt> mkdir jd-gui prompt> cd jd-gui prompt> prompt> tar xf jd-gui linux.i686.tar.gz prompt> jd-gui ~/.android os/dex2jar /first-dex2jar.jar Under silly.app.first click on MainActivity - the result is shown below 9

10 Extra stuff Uninstall the app prompt> adb uninstall silly.app.first Success Modify and re-install the app If eclipse is not open do this: prompt> ~/.android os/adt-bundle-linux/eclipse/eclipse Look at activity main.xml Drag a Button to the window Click on the button, edit Text in the Outline column on the right to Press Me Drag a TextView (Large) to the window Click on the Large Text, edit Text on the right to OK with me Right click on Hello World! and choose Delete Save Export as before to First.apk Install as before with adb Click on the app to get the picture on the left Click on the button to get the picture on the right 10