libfwumdata

A C library for handling Firmware Update (FWU) metadata, inspired by the U-Boot (fwumdata tool) and libubootenv implementations.

Overview

This library provides an interface to parse, validate (CRC32), and manipulate FWU metadata.

It was originally developed as a use case to allow tools such as SWUpdate, and in general any application, to modify the boot bank selection.

For this reason, the metadata manipulation APIs are currently minimal. They are designed to be exercised through the yafwumdata tool, which loosely mimics the behavior of the U-Boot fwumdata tool, with reduced functionality, intended to exercise the API through a command-line interface for a minimal set of operations, namely updating the active index, the previous active index, and the bank state.

Example: boot from bank B after a software update of the same bank.

yafwumdata -a 1 -p 0 -s 1 valid

This sets:

• the active index to bank B (-a 1)
• the previous active index to bank A (-p 0)
• the bank state to valid (-s 1 valid)

Licensing

This library is licensed under LGPL-2.1-or-later. Full license texts are available in the LICENSES/ directory.

Build Requirements

• CMake >= 3.12
• ZLIB development files (for CRC32 calculation)
• A C99 compliant compiler (GCC/Clang)

Quick Start

tar xf libfwumdata-<version>.tar.gz
cd libfwumdata-<version>
mkdir build && cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr/local ..
make
sudo make install

Testing

The library includes a unit testing framework to ensure the integrity of metadata operations. Tests are disabled by default and must be explicitly enabled during the configuration process.

tar xf libfwumdata-<version>.tar.gz
cd libfwumdata-<version>
mkdir build && cd build
cmake -DLIBFWUMDATA_BUILD_TESTS=ON ..
make
make test # or ctest

Maintainer

Dario Binacchi dario.binacchi@amarulasolutions.com