func (h *InHandler) handleHello(n *xn.Node) (err error) {
var (
m *XLatticeMsg
msgN uint64
id, ck, sk, sig, salt []byte
peer *xn.Peer
)
m, err = h.readMsg()
// message must be a Hello
if err == nil {
if m.GetOp() != XLatticeMsg_Hello {
err = MissingHello
}
}
if err == nil {
// the message is a hello; is its NodeID that of a known peer?
id = m.GetID()
if id == nil {
// DEBUG
fmt.Printf("handleHello: message has no ID field\n")
// END
err = NilPeer
} else {
peer, err = n.FindPeer(id)
if err == nil {
if peer == nil {
err = xn.NotAKnownPeer
} else {
h.Peer = peer
}
}
}
}
// On any error up to here silently close the connection and delete
// the handler.
if err != nil {
h.Cnx.Close()
h = nil
return
}
// message is a hello from a known peer -------------------------
// MsgN must be 1
msgN = m.GetMsgN()
h.MsgN = msgN
ck = m.GetCommsKey() // comms key as byte slice
sk = m.GetSigKey() // sig key as byte slice
salt = m.GetSalt()
sig = m.GetSig() // digital signature
var serCK, serSK []byte
if h.MsgN != 1 {
err = ExpectedMsgOne
}
if err == nil {
peerID := peer.GetNodeID().Value()
if !bytes.Equal(id, peerID) {
fmt.Println("NOT SAME NODE ID") // XXX should log
err = NotExpectedNodeID
}
}
if err == nil {
serCK, err = xc.RSAPubKeyToWire(peer.GetCommsPublicKey())
if err == nil {
if !bytes.Equal(serCK, ck) {
fmt.Println("NOT SAME COMMS KEY") // XXX should log
err = NotExpectedCommsKey
}
}
}
if err == nil {
serSK, err = xc.RSAPubKeyToWire(peer.GetSigPublicKey())
if err == nil {
if !bytes.Equal(serSK, sk) {
fmt.Println("NOT SAME SIG KEY") // XXX should log
err = NotExpectedSigKey
}
}
}
if err == nil {
sigPubKey := peer.GetSigPublicKey()
d := sha1.New()
d.Write(id)
d.Write(ck)
d.Write(sk)
d.Write(salt)
hash := d.Sum(nil)
err = rsa.VerifyPKCS1v15(sigPubKey, cr.SHA1, hash, sig)
}
if err == nil {
// Everything is good; so Ack, leaving cnx open.
h.Peer.MarkUp() // we consider the peer live
h.Peer.LastContact()
err = h.simpleAck(msgN)
} else {
// Send the text of the error to the peer; the send itself
// may of course cause an error, but we will ignore that.
// The peer is NOT marked as up.
h.errorReply(err)
}
return
}
