Android Open Source Project (AOSP) includes APN settings (apns-full-conf.xml) and carrier settings (carrier_config_*.xml + vendor.xml) in human-readable XML format. However, Google Pixel device images instead include APN and carrier settings as binary protobuf files for use by the CarrierSettings system app.
This script converts the CarrierSettings protobuf files (e.g., carrier_list.pb, others.pb) to XML format compatible with AOSP. This may be helpful for Android-based systems that do not bundle CarrierSettings, but wish to support carriers that are not included in AOSP.
Systems like GrapheneOS that do not ship proprietary google services and some other invasive apps need some cleanup for the carrierconfig vendor overlay. See generate-aosp-overlays.sh to see how these are generated
For a description of each APN and carrier setting, refer to the doc comments in Telephony.java and CarrierConfigManager.java, respectively.
- curl - required, for android-prepare-vendor
- e2fsprogs (debugfs) - required, for android-prepare-vendor
- git - required, for android-prepare-vendor
- protobuf-compiler (protoc) - optional, see below
- python3-protobuf - required
Download the carrier ID database from AOSP.
./download_carrier_list.sh
To download a Pixel factory image and extract the CarrierSettings protobuf files, use this script to download android-prepare-vendor and copy the directory CarrierSettings containing the protobuf files.
DEVICE=crosshatch BUILD=QQ3A.200605.001 ./download_factory_img.sh
You can get the build IDs from here
Convert CarrierSettings/*.pb to apns-full-conf.xml and vendor.xml (see below for cleaning this output).
./carriersettings_extractor.py CarrierSettings
Copy apns-full-conf.xml to the device tree (device/google/$DEVICE)
To clean up the vendor overlays run this command
bash generate-aosp-overlays.sh
This command assumes that the other steps were followed exactly as they were written here. The cleanup script will fail unless the factory image and carrierlist are already downloaded
Copy vendor.xml to the device tree overlays dir, example device/google/$DEVICE/overlay/packages/apps/CarrierConfig/res/xml/vendor.xml
In some cases that path may not be the right one, use device/google/<device-family-common-name>/$DEVICE/overlay/packages/apps/CarrierConfig/res/xml/vendor.xml and an example is here
The definitions in carriersettings.proto are useful for inspecting the CarrierSettings protobuf files.
protoc --decode=CarrierList carriersettings.proto < CarrierSettings/carrier_list.pb
protoc --decode=CarrierSettings carriersettings.proto < CarrierSettings/verizon_us.pb
protoc --decode=MultiCarrierSettings carriersettings.proto < CarrierSettings/others.pb
To check schema or otherwise inspect the protobuf files without applying definitions, use the --decode_raw argument.
protoc --decode_raw < CarrierSettings/carrier_list.pb
protoc --decode_raw < CarrierSettings/verizon_us.pb
protoc --decode_raw < CarrierSettings/others.pb