wolfCOSE is a lightweight C library for implementing CBOR and COSE protocols using wolfSSL as the crypto backend. It supports all six COSE message types, including multi-signer and multi-recipient messages, and post-quantum signing with ML-DSA at three security levels.
The library has a tiny footprint of 7.5 KB in minimal build mode and 25.6 KB in full build mode, making it suitable for resource-constrained devices. It also requires zero dynamic allocation, using caller-provided buffers instead. wolfCOSE is compatible with FIPS 140-3 via the wolfCrypt FIPS Certificate.
The library supports a wide range of algorithms, including ES256, ES384, and PS512 for signing, AES-GCM and ChaCha20-Poly1305 for encryption, HMAC-SHA256/384/512, and AES-MAC for MAC operations. It also includes direct key distribution, AES Key Wrap, and ECDH-ES+HKDF.
wolfCOSE is available under the GPLv3 license and can be built on Ubuntu, macOS, with GCC 10-14 or Clang 14-18 compilers. The library comes with a comprehensive test suite, including ~240 algorithm combination tests, and has achieved 99.3% code coverage.
