com.google.crypto.tink.mac

Interface ChunkedMacComputation

public interface ChunkedMacComputation

An interface representing a computation of the Streaming MAC.

WARNING: Implementations of this interface are not thread-safe, so the caller must ensure correctness in case of concurrent use of an instance of this class.

Method Summary

Modifier and Type	Method and Description
byte[]	computeMac() Computes a tag for the provided data.
void	update(ByteBuffer data) Processes the next chunk of input, represented by ByteBuffer data.

Method Detail

update

void update(ByteBuffer data)
     throws GeneralSecurityException

Processes the next chunk of input, represented by ByteBuffer data. In particular, reads the data.remaining() number of bytes from the provided buffer, starting at the byte with position data.position().

Updates the inner state of the computation. Requires exclusive access.

NOTE: arbitrary slicing of data is permitted, i.e. a series of update()'s with inputs "ab", "cd", and "ef" produces the same result as a series of inputs "abc", "def".

Throws:

IllegalStateException - if called after computeMac()

GeneralSecurityException - when something went wrong with the update

computeMac

byte[] computeMac()
           throws GeneralSecurityException

Computes a tag for the provided data. After this method has been called, the object can no longer be used.

Requires exclusive access.

Throws:

IllegalStateException - when called more than once

GeneralSecurityException - when something went wrong with the computation