aesgcm

func Open ¶

func Open(key []byte, packed []byte) (plaintext, extra []byte, err error)

produce the plaintext and extra data from the packet created by Seal

The key must be the same as the one used for encryption. Produce an error if the message cannot be authenticated.

func Seal ¶

func Seal(key, plaintext, extra []byte) (msg []byte, err error)

produce a packet

signature: "aGCM"
noncelen: uint8(12)
extralen: uint8
nonce: radomly generated
extra:
sealed: plaintext authenticated and encrypted with key
        extra is also authenticated

Note that the design of crypto/cipher.AEAD makes it difficult at best
to create a streaming interface. We are stuck with a message-oriented
protocol unless we want to reimplement the GCM.  This may or may not
be a bad thing.