Mbed TLS
A C library implementing X.509 certificate handling and the TLS and DTLS protocols, with a small code footprint intended for embedded systems, plus a PSA Cryptography API implementation.
Mbed TLS is a C library that implements X.509 certificate manipulation and the TLS and DTLS protocols, with a small code footprint that suits embedded systems. It includes the TF-PSA-Crypto repository, which provides an implementation of the PSA Cryptography API.
X.509 and TLS options are configured through a header file, while cryptography and platform options live in a separate TF-PSA-Crypto configuration file; both can be edited by hand or through a bundled Python configuration script, and a configs directory documents non-standard configurations for specific use cases. The project uses CMake to build three libraries, libtfpsacrypto, libmbedx509, and libmbedtls, with libmbedtls depending on the other two, and generates its API documentation with Doxygen.