func BuildCircuit(slc []dirclient.KNode, subchannel int) (io.ReadWriteCloser, error) {
// this returns a checker whether a public key is valid
pubkey_checker := func(hsh string) func([]byte) bool {
return func([]byte) bool { return true }
return func(xaxa []byte) bool {
hashed := hash_base32(xaxa)
return subtle.ConstantTimeCompare([]byte(hashed), []byte(hsh)) == 1
}
}
// circuit-building loop
gwire, err := dialer.Dial(Old2New(slc[0].Address))
if err != nil {
return nil, err
}
wire, err := kiss.TransportHandshake(kiss.GenerateDHKeys(),
gwire, pubkey_checker(slc[0].PublicKey))
if err != nil {
gwire.Close()
return nil, err
}
for _, ele := range slc[1:] {
kilog.Debug("Connecting to node %v...", string([]byte(ele.PublicKey)[:10]))
// extend wire
_, err = wire.Write(append([]byte{byte(len(ele.PublicKey))}, ele.PublicKey...))
if err != nil {
gwire.Close()
return nil, err
}
verifier := pubkey_checker(ele.PublicKey)
// at this point wire is raw (well unobfs) connection to next
wire, err = kiss.TransportHandshake(kiss.GenerateDHKeys(), wire, verifier)
if err != nil {
kilog.Debug("Died when transport at %s", ele.PublicKey)
gwire.Close()
return nil, err
}
kilog.Debug("Connected to node %v!", string([]byte(ele.PublicKey)[:10]))
}
_, err = wire.Write([]byte{byte(subchannel)})
if err != nil {
gwire.Close()
return nil, err
}
kilog.Debug("Opened subchannel %d", subchannel)
return wire, nil
}
func sc_server_real_handler(_wire io.ReadWriteCloser) (err error) {
wire, err := kiss.TransportHandshake(MasterKey, _wire,
func([]byte) bool { return true })
if err != nil {
kilog.Debug("failed the transport handshake")
return err
}
thing := make([]byte, 1)
_, err = io.ReadFull(wire, thing)
if err != nil {
kilog.Debug("failed the readfull")
return err
}
if thing[0] == 0 {
// Terminate
if !MasterConfig.General.IsExit {
return nil
}
kilog.Debug("opening legacy (stew) circuit")
e2e_server_handler_old(wire)
} else if thing[0] == 255 {
// Terminate with kinda old
if !MasterConfig.General.IsExit {
return nil
}
kilog.Debug("opening kinda old circuit")
e2e_server_kinda_old_handler(wire)
} else if thing[0] == 254 {
// Terminate with new
if !MasterConfig.General.IsExit {
return nil
}
kilog.Debug("opening circuit")
e2e_server_handler(wire)
} else {
xaxa := make([]byte, thing[0])
_, err := io.ReadFull(wire, xaxa)
if err != nil {
return err
}
key := string(xaxa)
qqq := dirclient.PKeyLookup(key)
if qqq == nil {
kilog.Debug("Cannot find %s in %v", xaxa, dirclient.KDirectory)
dirclient.RefreshDirectory()
qqq = dirclient.PKeyLookup(key)
if qqq == nil {
return nil
}
}
kilog.Debug("Continuing to %s", qqq.Address)
remm, err := circuitry.Dialer.Dial(circuitry.Old2New(qqq.Address))
if err != nil {
return err
}
go func() {
io.Copy(wire, remm)
wire.Close()
}()
io.Copy(remm, wire)
remm.Close()
}
return io.EOF
}