Does openSSL support the TLS 1.2 with delegation of crypto operations to HSM using PKCS#11?

[pist-eb]

Hi Everyone,

TLS 1.2 facilitates cipher suites that rely on the prior exchange of a shared secret for symmetric (bulk) encryption and the storage of pre-shared keys (PSK) by communication parties (e.g., TLS_PSK_WITH_AES_128_GCM_SHA256). In such scenarios, it's crucial to securely store the pre-shared key, ideally within a Hardware Security Module (HSM) available in the platform/system.

For security reasons, it's essential that the pre-shared key never leaves the HSM, and all operations utilizing the PSK occur within a trusted environment. In the context of the TLS protocol, key derivation using the pre-shared key should be delegated to the HSM, with only the calculated TLS session key used outside of it. A similar approach could be applied to signing and verifying the Finished message. The PKCS#11 interface is typically used to achieve this goal.

OpenSSL supports engines (pre-3.0) and providers (3.0 onwards).

• Does OpenSSL currently support TLS 1.2 with PSK while delegating crypto operations (such as session key derivation, signing, and verifying the Finished message) to an HSM using engines/providers?

• If not, does this feature sound reasonable enough to be considered for inclusion in the roadmap?

Thank you for your support!