I am working on a project involving distributed radio nodes connected over a wireless network. We are using symmetric key cryptography for ciphering (AES-256). The radio nodes are running Linux on a 250MHz processor.

I need a solution to manage the symmetric keys in this network of nodes, written in C/C++. The solution should be able to manage the life cycle of the keys. It should be able to auto-generate a new key (upon expiry or when manually instructed by the user) and securely disseminate it in the network and archive the old key after activation of the new key.

I have looked at Key Management Interoperability Protocol (KMIP). It provides all of these features but sadly there is no open-source implementation available in C.

Does anyone know a solution for symmetric key management that can provide these features and implemented in the open-source domain?

Thanks,

Usman