System.Security.Cryptography.CngKeyUsages
Specifies the cryptographic operations that a Cryptography Next Generation (CNG) key may be used with.
AllUsages = 16777215
The key can be used for all purposes.
Decryption = 1
The key can be used for encryption and decryption.
KeyAgreement = 4
The key can be used for secret agreement generation and key exchange.
None = 0
No usage values are assigned to the key.
Signing = 2
The key can be used for signing and verification.