args.go

/*
MIT License

Copyright (c) 2023 Lonny Wong <lonnywong@qq.com>

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

package tssh

import (
	"fmt"
	"strings"
)

type sshOption struct {
	options map[string]string
}

type multiStr struct {
	values []string
}

type bindArgs struct {
	binds []*bindCfg
}

type forwardArgs struct {
	cfgs []*forwardCfg
}

type sshArgs struct {
	Ver            bool        `arg:"-V,--" help:"show program's version number and exit"`
	Destination    string      `arg:"positional" help:"alias in ~/.ssh/config, or [user@]hostname[:port]"`
	Command        string      `arg:"positional" help:"command to execute instead of a login shell"`
	Argument       []string    `arg:"positional" help:"command arguments separated by spaces"`
	DisableTTY     bool        `arg:"-T,--" help:"disable pseudo-terminal allocation"`
	ForceTTY       bool        `arg:"-t,--" help:"force pseudo-terminal allocation"`
	Gateway        bool        `arg:"-g,--" help:"forwarding allows remote hosts to connect"`
	Background     bool        `arg:"-f,--" help:"run as a background process, implies -n"`
	NoCommand      bool        `arg:"-N,--" help:"do not execute a remote command"`
	Port           int         `arg:"-p,--" placeholder:"port" help:"port to connect to on the remote host"`
	LoginName      string      `arg:"-l,--" placeholder:"login_name" help:"the user to log in as on the remote machine"`
	Identity       multiStr    `arg:"-i,--" placeholder:"identity_file" help:"identity (private key) for public key auth"`
	ProxyJump      string      `arg:"-J,--" placeholder:"destination" help:"jump hosts separated by comma characters"`
	Option         sshOption   `arg:"-o,--" placeholder:"key=value" help:"options in the format used in ~/.ssh/config\ne.g., tssh -o ProxyCommand=\"ssh proxy nc %h %p\""`
	StdioForward   string      `arg:"-W,--" placeholder:"host:port" help:"forward stdin and stdout to host on port"`
	DynamicForward bindArgs    `arg:"-D,--" placeholder:"[bind_addr:]port" help:"dynamic port forwarding ( socks5 proxy )"`
	LocalForward   forwardArgs `arg:"-L,--" placeholder:"[bind_addr:]port:host:hostport" help:"local port forwarding"`
	RemoteForward  forwardArgs `arg:"-R,--" placeholder:"[bind_addr:]port:host:hostport" help:"remote port forwarding"`
	DragFile       bool        `arg:"--dragfile" help:"enable drag files and directories to upload"`
	TraceLog       bool        `arg:"--tracelog" help:"enable trzsz detect trace logs for debugging"`
	Relay          bool        `arg:"--relay" help:"force trzsz run as a relay on the jump server"`
	Debug          bool        `arg:"--debug" help:"verbose mode for debugging, same as ssh's -vvv"`
}

func (sshArgs) Description() string {
	return "Simple ssh client with trzsz ( trz / tsz ) support.\n"
}

func (sshArgs) Version() string {
	return fmt.Sprintf("trzsz ssh %s", kTsshVersion)
}

func (o *sshOption) UnmarshalText(b []byte) error {
	s := string(b)
	pos := strings.Index(s, "=")
	if pos < 1 {
		return fmt.Errorf("invalid option: %s", s)
	}
	if o.options == nil {
		o.options = make(map[string]string)
	}
	o.options[strings.ToLower(strings.TrimSpace(s[:pos]))] = strings.TrimSpace(s[pos+1:])
	return nil
}

func (o *sshOption) get(option string) string {
	if o.options == nil {
		return ""
	}
	return o.options[strings.ToLower(option)]
}

func (v *multiStr) UnmarshalText(b []byte) error {
	v.values = append(v.values, string(b))
	return nil
}

func (a *bindArgs) UnmarshalText(b []byte) error {
	bind, err := parseBindCfg(string(b))
	if err != nil {
		return err
	}
	a.binds = append(a.binds, bind)
	return nil
}

func (f *forwardArgs) UnmarshalText(b []byte) error {
	arg, err := parseForwardArg(string(b))
	if err != nil {
		return err
	}
	f.cfgs = append(f.cfgs, arg)
	return nil
}