GetData Method

GetData()

Gets the signature, or decrypted data, or key agreement shared secret from the YubiKey response.

C#
public byte[] GetData()

Returns

System.Byte[]

The signature, decrypted data, or key agreement shared secret as a byte array.

Implements

Exceptions

Type Condition
System.InvalidOperationException

Thrown when Status is not Success.

Remarks

Note that the data returned can be sensitive data. It is a new byte array, belonging to the caller. The caller should overwrite this memory as soon as it is no longer needed, using CryptographicOperations.ZeroMemory.

The data returned by the YubiKey is encoded as follows. 

  7C L1 { 82 L2 result }

The GetData method returns the decoded data, returning the result.

For an RSA signature, it will appear to be random bytes. There are no tags, no length octets, just the signature.

For an ECC signature, it will be the DER encoding of 

   SEQUENCE {
     r   INTEGER,
     s   INTEGER
   }

If the data returned by the YubiKey is decrypted data, it is returned as the formatted plaintext.

If the data returned by the YubiKey is the key agreement shared secret, it is the raw secret bytes.

Note that if there is no data to return, this method will throw an exception. Even if the response indicates AuthenticationRequired (see the Status property), which means the process was not completed because the wrong or no PIN was entered, or the YubiKey was not touched within the time period. That is, it is not an error, the process is simply incomplete. Nonetheless, in that case the method will throw an exception. Hence, do not call this method unless you know that Status is Success.