// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package ssh

import (
	
	
)

// OpenChannelError is returned if the other side rejects an
// OpenChannel request.
type OpenChannelError struct {
	Reason  RejectionReason
	Message string
}

func ( *OpenChannelError) () string {
	return fmt.Sprintf("ssh: rejected: %s (%s)", .Reason, .Message)
}

// ConnMetadata holds metadata for the connection.
type ConnMetadata interface {
	// User returns the user ID for this connection.
	User() string

	// SessionID returns the session hash, also denoted by H.
	SessionID() []byte

	// ClientVersion returns the client's version string as hashed
	// into the session ID.
	ClientVersion() []byte

	// ServerVersion returns the server's version string as hashed
	// into the session ID.
	ServerVersion() []byte

	// RemoteAddr returns the remote address for this connection.
	RemoteAddr() net.Addr

	// LocalAddr returns the local address for this connection.
	LocalAddr() net.Addr
}

// Conn represents an SSH connection for both server and client roles.
// Conn is the basis for implementing an application layer, such
// as ClientConn, which implements the traditional shell access for
// clients.
type Conn interface {
	ConnMetadata

	// SendRequest sends a global request, and returns the
	// reply. If wantReply is true, it returns the response status
	// and payload. See also RFC 4254, section 4.
	SendRequest(name string, wantReply bool, payload []byte) (bool, []byte, error)

	// OpenChannel tries to open an channel. If the request is
	// rejected, it returns *OpenChannelError. On success it returns
	// the SSH Channel and a Go channel for incoming, out-of-band
	// requests. The Go channel must be serviced, or the
	// connection will hang.
	OpenChannel(name string, data []byte) (Channel, <-chan *Request, error)

	// Close closes the underlying network connection
	Close() error

	// Wait blocks until the connection has shut down, and returns the
	// error causing the shutdown.
	Wait() error

	// TODO(hanwen): consider exposing:
	//   RequestKeyChange
	//   Disconnect
}

// DiscardRequests consumes and rejects all requests from the
// passed-in channel.
func ( <-chan *Request) {
	for  := range  {
		if .WantReply {
			.Reply(false, nil)
		}
	}
}

// A connection represents an incoming connection.
type connection struct {
	transport *handshakeTransport
	sshConn

	// The connection protocol.
	*mux
}

func ( *connection) () error {
	return .sshConn.conn.Close()
}

// sshConn provides net.Conn metadata, but disallows direct reads and
// writes.
type sshConn struct {
	conn net.Conn

	user          string
	sessionID     []byte
	clientVersion []byte
	serverVersion []byte
}

func dup( []byte) []byte {
	 := make([]byte, len())
	copy(, )
	return 
}

func ( *sshConn) () string {
	return .user
}

func ( *sshConn) () net.Addr {
	return .conn.RemoteAddr()
}

func ( *sshConn) () error {
	return .conn.Close()
}

func ( *sshConn) () net.Addr {
	return .conn.LocalAddr()
}

func ( *sshConn) () []byte {
	return dup(.sessionID)
}

func ( *sshConn) () []byte {
	return dup(.clientVersion)
}

func ( *sshConn) () []byte {
	return dup(.serverVersion)
}