// Encrypt encryptes the given UID message.
func (msg *Message) Encrypt() (UIDHash, UIDIndex []byte, UIDMessageEncrypted string) {
Message := msg.JSON()
// Calculate hash: UIDHash = sha256(UIDMessage)
UIDHash = cipher.SHA256(Message)
// Calculate hash: UIDIndex = sha256(UIDHash)
UIDIndex = cipher.SHA256(UIDHash)
// Encrypt UIDMessage: UIDMessageEncrypted = UIDIndex | nonce | aes_ctr(nonce, key=UIDHash, UIDMessage)
enc := cipher.AES256CTREncrypt(UIDHash, Message, cipher.RandReader)
uidEnc := make([]byte, sha256.Size+len(enc))
copy(uidEnc, UIDIndex)
copy(uidEnc[sha256.Size:], enc)
UIDMessageEncrypted = base64.Encode(uidEnc)
return
}
func (msg *Message) sessionAnchor(
key []byte,
mixaddress, nymaddress string,
rand io.Reader,
) (sessionAnchor, sessionAnchorHash, pubKeyHash, privateKey string, err error) {
var sa SessionAnchor
sa.MIXADDRESS = mixaddress
sa.NYMADDRESS = nymaddress
sa.PFKEYS = make([]KeyEntry, 1)
if err := sa.PFKEYS[0].InitDHKey(rand); err != nil {
return "", "", "", "", err
}
jsn := sa.json()
hash := cipher.SHA512(jsn)
// SESSIONANCHOR = AES256_CTR(key=UIDMessage.UIDContent.SIGKEY.HASH, SessionAnchor)
enc := base64.Encode(cipher.AES256CTREncrypt(key[:32], jsn, rand))
return enc, base64.Encode(hash), sa.PFKEYS[0].HASH, base64.Encode(sa.PFKEYS[0].PrivateKey32()[:]), nil
}