mozilla-services/zipalign

DEPRECATED - Golang implementation of Android's ZipAlign tool

ZipAlign

A Go replacement for Android's SDK ZipAlign tool. See https://developer.android.com/studio/command-line/zipalign.html for more information.

When signing an APK with jarsigner, the returned zip is not aligned properly. Android optimizes APK by aligning each file on 4 bytes to load them with mmap. Running zipalign on an unaligned APK fixes its padding in the headers of each entry to align it properly.

Installation: go get github.com/mozilla-services/zipalign

Usage: zipalign -a 4 -i infile.zip -o outfile.zip

Example

The command below takes a signed unaligned apk and fixes its padding. Verbosity is reduced to only show files that require padding. The aligned APK is then verified with Android's original zipalign tool to make sure the alignment is correct per Android standard.

$ zipalign -i ~/app-rocket-webkit-release-1816-signed.apk -o /tmp/rocket-aligned.signed.apk -v 2>&1| grep padding

2018/01/11 08:16:59  --- res/drawable-hdpi-v4/common_google_signin_btn_icon_dark_normal_background.9.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-hdpi-v4/design_ic_visibility.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-hdpi-v4/googleg_disabled_color_18.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-hdpi-v4/home_pattern.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-hdpi-v4/ic_notification.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-hdpi-v4/logotype.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-mdpi-v4/common_google_signin_btn_icon_dark_normal_background.9.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-mdpi-v4/design_ic_visibility.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-mdpi-v4/googleg_disabled_color_18.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-mdpi-v4/notification_bg_low_normal.9.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-xhdpi-v4/common_google_signin_btn_icon_dark_normal_background.9.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-xhdpi-v4/design_ic_visibility.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-xhdpi-v4/googleg_disabled_color_18.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-xhdpi-v4/notification_bg_low_normal.9.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-xxhdpi-v4/common_google_signin_btn_icon_dark_normal_background.9.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-xxhdpi-v4/design_ic_visibility.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-xxhdpi-v4/googleg_disabled_color_18.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-xxhdpi-v4/home_pattern.png: padding 1 bytes
2018/01/11 08:16:59  --- res/drawable-xxhdpi-v4/ic_notification.png: padding 3 bytes
2018/01/11 08:16:59  --- res/drawable-xxhdpi-v4/logotype.png: padding 1 bytes

$ /opt/android-sdk/build-tools/27.0.3/zipalign -c -v 4 /tmp/rocket-aligned.signed.apk
...
Verification succesful

zipalign's Issues

CODE_OF_CONDUCT.md file missing

As of January 1 2019, Mozilla requires that all GitHub projects include this CODE_OF_CONDUCT.md file in the project root. The file has two parts:

1. Required Text - All text under the headings Community Participation Guidelines and How to Report, are required, and should not be altered.
2. Optional Text - The Project Specific Etiquette heading provides a space to speak more specifically about ways people can work effectively and inclusively together. Some examples of those can be found on the Firefox Debugger project, and Common Voice. (The optional part is commented out in the raw template file, and will not be visible until you modify and uncomment that part.)

If you have any questions about this file, or Code of Conduct policies and procedures, please reach out to [email protected].

(Message COC001)