// ReceiveFromMix decrypts a message received from the mix
func ReceiveFromMix(receiveTemplate nymaddr.AddressTemplate, MailboxAddress, msg []byte) (decMessage, Nym []byte, err error) {
if len(msg) < 2 {
return nil, nil, ErrTooShort
}
headerLen := int(binary.BigEndian.Uint16(msg[0:2]))
if len(msg) < 2+headerLen {
return nil, nil, ErrTooShort
}
headerContent := msg[2 : 2+headerLen]
nym, secret, err := receiveTemplate.GetPrivate(headerContent, MailboxAddress)
if err != nil {
return nil, nil, err
}
nonce := sha256.Sum256(headerContent)
decMessage, err = GCMDecrypt(nonce[:], secret, msg[2+headerLen:])
if err != nil {
return nil, nil, err
}
return decMessage, nym, nil
}
