MrAle98-sliver/client/command/shell.go

package command

/*
	Sliver Implant Framework
	Copyright (C) 2019  Bishop Fox

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

import (
	"context"
	"fmt"
	"io"
	"log"
	"os"

	"github.com/bishopfox/sliver/client/core"
	"github.com/bishopfox/sliver/protobuf/rpcpb"
	"github.com/bishopfox/sliver/protobuf/sliverpb"

	"github.com/desertbit/grumble"
	"golang.org/x/crypto/ssh/terminal"
)

const (
	windows = "windows"
)

func shell(ctx *grumble.Context, rpc rpcpb.SliverRPCClient) {
	session := ActiveSession.GetInteractive()
	if session == nil {
		return
	}

	if !isUserAnAdult() {
		return
	}

	shellPath := ctx.Flags.String("shell-path")
	noPty := ctx.Flags.Bool("no-pty")
	if ActiveSession.Get().OS == windows {
		noPty = true // Windows of course doesn't have PTYs
	}
	runInteractive(shellPath, noPty, rpc)
}

func runInteractive(shellPath string, noPty bool, rpc rpcpb.SliverRPCClient) {
	fmt.Printf(Info + "Opening shell tunnel (EOF to exit) ...\n\n")

	session := ActiveSession.Get()
	stream, err := rpc.Shell(context.Background())
	stream.Send(&sliverpb.ShellTunnel{
		SessionID: session.ID,
		EnablePTY: !noPty,
		Path:      shellPath,
	})
	if err != nil {
		fmt.Printf(Warn+"%s\n", err)
		return
	}

	tunnel := &core.Tunnel{
		SessionID: session.ID,
		Send:      make(chan []byte),
		Recv:      make(chan []byte),
	}

	go func() {
		for {
			incoming, err := stream.Recv()
			if err == io.EOF {
				tunnel.Close()
				return
			}
			tunnel.Recv <- incoming.Data
		}
	}()

	go func() {
		for data := range tunnel.Send {
			stream.Send(&sliverpb.ShellTunnel{
				Data: data,
			})
		}
	}()

	var oldState *terminal.State
	if !noPty {
		oldState, err = terminal.MakeRaw(0)
		log.Printf("Saving terminal state: %v", oldState)
		if err != nil {
			fmt.Printf(Warn + "Failed to save terminal state")
			return
		}
	}

	go func() {
		_, err := io.Copy(os.Stdout, tunnel)
		if err != nil {
			fmt.Printf(Warn+"Error writing to stdout: %v", err)
			return
		}
	}()
	for {
		_, err := io.Copy(tunnel, os.Stdin)
		if err == io.EOF {
			break
		}
		if err != nil {
			fmt.Printf(Warn+"Error reading from stdin: %v", err)
			break
		}
	}

	if !noPty {
		terminal.Restore(0, oldState)
	}
}