List of Key Usages supported by FDE smart card authentication

Digital signature

Use when the public key is used with a digital signature mechanism to support security services other than non-repudiation, certificate signing, or CRL signing. A digital signature is often used for entity authentication and data origin authentication with integrity.

Non-repudiation

Use when the public key is used to verify digital signatures used to provide a non-repudiation service. Non-repudiation protects against the signing entity falsely denying some action (excluding certificate or CRL signing).

Key encipherment

Use when a certificate will be used with a protocol that encrypts keys. An example is S/MIME enveloping, where a fast (symmetric) key is encrypted with the public key from the certificate. SSL protocol also performs key encipherment.

Data encipherment

Use when the public key is used for encrypting user data, other than cryptographic keys.

Key agreement

Use when the sender and receiver of the public key need to derive the key without using encryption. This key can then be used to encrypt messages between the sender and receiver. Key agreement is typically used with Diffie-Hellman ciphers.

Encipher only

Use only when key agreement is also enabled. This enables the public key to be used only for enciphering data while performing key agreement.