cwtch/protocol/connections/fetch/peer_fetch_channel.go

104 lines
3.2 KiB
Go

package fetch
import (
"cwtch.im/cwtch/protocol"
"errors"
"git.openprivacy.ca/openprivacy/libricochet-go/channels"
"git.openprivacy.ca/openprivacy/libricochet-go/utils"
"git.openprivacy.ca/openprivacy/libricochet-go/wire/control"
"github.com/golang/protobuf/proto"
)
// CwtchPeerFetchChannel is the peer implementation of the im.cwtch.server.fetch
// channel.
type CwtchPeerFetchChannel struct {
channel *channels.Channel
Handler CwtchPeerFetchChannelHandler
}
// CwtchPeerFetchChannelHandler should be implemented by peers to receive new messages.
type CwtchPeerFetchChannelHandler interface {
HandleGroupMessage(*protocol.GroupMessage)
}
// Type returns the type string for this channel, e.g. "im.ricochet.server.fetch)
func (cpfc *CwtchPeerFetchChannel) Type() string {
return "im.cwtch.server.fetch"
}
// Closed is called when the channel is closed for any reason.
func (cpfc *CwtchPeerFetchChannel) Closed(err error) {
}
// OnlyClientCanOpen - for Cwtch server channels only client can open
func (cpfc *CwtchPeerFetchChannel) OnlyClientCanOpen() bool {
return true
}
// Singleton - for Cwtch channels there can only be one instance per direction
func (cpfc *CwtchPeerFetchChannel) Singleton() bool {
return true
}
// Bidirectional - for Cwtch channels are not bidrectional
func (cpfc *CwtchPeerFetchChannel) Bidirectional() bool {
return false
}
// RequiresAuthentication - Cwtch server channels require no auth.
func (cpfc *CwtchPeerFetchChannel) RequiresAuthentication() string {
return "none"
}
// OpenInbound - cwtch server peer implementations shouldnever respond to inbound requests
func (cpfc *CwtchPeerFetchChannel) OpenInbound(channel *channels.Channel, raw *Protocol_Data_Control.OpenChannel) ([]byte, error) {
return nil, errors.New("client does not receive inbound listen channels")
}
// OpenOutbound sets up a new cwtch fetch channel
func (cpfc *CwtchPeerFetchChannel) OpenOutbound(channel *channels.Channel) ([]byte, error) {
cpfc.channel = channel
messageBuilder := new(utils.MessageBuilder)
return messageBuilder.OpenChannel(channel.ID, cpfc.Type()), nil
}
// OpenOutboundResult confirms a previous open channel request
func (cpfc *CwtchPeerFetchChannel) OpenOutboundResult(err error, crm *Protocol_Data_Control.ChannelResult) {
if err == nil {
if crm.GetOpened() {
cpfc.channel.Pending = false
cpfc.FetchRequest()
}
}
}
// FetchRequest sends a FetchMessage to the Server.
func (cpfc *CwtchPeerFetchChannel) FetchRequest() error {
if cpfc.channel.Pending == false {
fm := &protocol.FetchMessage{}
csp := &protocol.CwtchServerPacket{
FetchMessage: fm,
}
packet, _ := proto.Marshal(csp)
cpfc.channel.SendMessage(packet)
} else {
return errors.New("channel isn't set up yet")
}
return nil
}
// Packet is called for each raw packet received on this channel.
func (cpfc *CwtchPeerFetchChannel) Packet(data []byte) {
csp := &protocol.CwtchServerPacket{}
err := proto.Unmarshal(data, csp)
if err == nil {
if csp.GetGroupMessage() != nil {
gm := csp.GetGroupMessage()
// We create a new go routine here to avoid leaking any information about processing time
// TODO Server can probably try to use this to DoS a peer
go cpfc.Handler.HandleGroupMessage(gm)
}
}
}