81 lines
1.7 KiB
Go
81 lines
1.7 KiB
Go
// Copyright 2011 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package ssh
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// A Terminal is capable of parsing and generating virtual terminal
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// data from an SSH client.
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type Terminal interface {
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ReadLine() (line string, err error)
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SetSize(x, y int)
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Write([]byte) (int, error)
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}
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// ServerTerminal contains the state for running a terminal that is capable of
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// reading lines of input.
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type ServerTerminal struct {
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Term Terminal
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Channel Channel
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}
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// parsePtyRequest parses the payload of the pty-req message and extracts the
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// dimensions of the terminal. See RFC 4254, section 6.2.
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func parsePtyRequest(s []byte) (width, height int, ok bool) {
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_, s, ok = parseString(s)
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if !ok {
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return
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}
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width32, s, ok := parseUint32(s)
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if !ok {
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return
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}
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height32, _, ok := parseUint32(s)
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width = int(width32)
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height = int(height32)
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if width < 1 {
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ok = false
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}
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if height < 1 {
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ok = false
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}
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return
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}
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func (ss *ServerTerminal) Write(buf []byte) (n int, err error) {
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return ss.Term.Write(buf)
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}
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// ReadLine returns a line of input from the terminal.
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func (ss *ServerTerminal) ReadLine() (line string, err error) {
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for {
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if line, err = ss.Term.ReadLine(); err == nil {
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return
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}
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req, ok := err.(ChannelRequest)
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if !ok {
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return
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}
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ok = false
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switch req.Request {
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case "pty-req":
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var width, height int
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width, height, ok = parsePtyRequest(req.Payload)
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ss.Term.SetSize(width, height)
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case "shell":
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ok = true
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if len(req.Payload) > 0 {
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// We don't accept any commands, only the default shell.
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ok = false
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}
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case "env":
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ok = true
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}
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if req.WantReply {
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ss.Channel.AckRequest(ok)
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}
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}
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panic("unreachable")
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}
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