Only latest client was active at ssh server. Added Callback so user can manage rpc clients

This commit is contained in:
Justin 2015-04-07 00:07:57 -04:00
parent 5dfe2ab054
commit 91d8c1f8ab

View File

@ -15,13 +15,16 @@ const DefaultRPCChannel = "RPCChannel"
// RPCSubsystem is the subsystem that will be used to trigger RPC endpoint creation
const RPCSubsystem = "RPCSubsystem"
// CallbackFunc to be called when reverse RPC client is created
type CallbackFunc func(RPCClient *rpc.Client)
// Server represents an SSH Server that spins up RPC servers when requested.
type Server struct {
*rpc.Server
Config *ssh.ServerConfig
ChannelName string
RPCClient *rpc.Client
sshConn ssh.Conn
CallbackFunc
}
// NewServer returns a new Server to handle incoming SSH and RPC requests.
@ -34,7 +37,7 @@ func NewServer() *Server {
return nil, fmt.Errorf("password rejected for %q", c.User())
},
}
return &Server{rpc.NewServer(), c, DefaultRPCChannel, nil, nil}
return &Server{Server: rpc.NewServer(), Config: c, ChannelName: DefaultRPCChannel}
}
@ -57,7 +60,7 @@ func (s *Server) StartServer(address string) {
}
// Before use, a handshake must be performed on the incoming net.Conn.
sshConn, chans, reqs, err := ssh.NewServerConn(tcpConn, s.Config)
s.sshConn = sshConn
if err != nil {
log.Printf("failed to handshake (%s)", err)
continue
@ -67,7 +70,7 @@ func (s *Server) StartServer(address string) {
// Print incoming out-of-band Requests
go s.handleRequests(reqs)
// Accept all channels
go s.handleChannels(chans)
go s.handleChannels(chans, sshConn)
}
}
@ -80,7 +83,7 @@ func (s *Server) handleRequests(reqs <-chan *ssh.Request) {
}
// handleChannels handels SSH Channel requests and their local out-of-band SSH Requests
func (s *Server) handleChannels(chans <-chan ssh.NewChannel) {
func (s *Server) handleChannels(chans <-chan ssh.NewChannel, sshConn ssh.Conn) {
// Service the incoming Channel channel.
for newChannel := range chans {
@ -105,19 +108,22 @@ func (s *Server) handleChannels(chans <-chan ssh.NewChannel) {
case "subsystem":
ok = true
log.Printf("subsystem '%s'", req.Payload)
log.Printf("subsystem '%s'", req.Payload[4:])
switch string(req.Payload[4:]) {
//RPCSubsystem Request made indicates client desires RPC Server access
case RPCSubsystem:
go s.ServeConn(channel)
log.Printf("Started SSH RPC")
// triggers reverse RPC connection as well
clientChannel, err := openRPCClientChannel(s.sshConn, s.ChannelName+"-reverse")
clientChannel, err := openRPCClientChannel(sshConn, s.ChannelName+"-reverse")
if err != nil {
log.Printf("Failed to create client channel: " + err.Error())
continue
}
s.RPCClient = rpc.NewClient(clientChannel)
rpcClient := rpc.NewClient(clientChannel)
if s.CallbackFunc != nil {
s.CallbackFunc(rpcClient)
}
log.Printf("Started SSH RPC client")
default:
log.Printf("Unknown subsystem: %s", req.Payload)