exec/proot/proot_linux.go

//go:build linux || android

package proot

import (
	"context"
	"os"
	"os/exec"
	"runtime"
	"syscall"

	goexec "sirherobrine23.com.br/go-bds/exec/exec"
)

const (
	DISABLED = iota
	DISABLING
	ENABLED

	FILTER_SYSEXIT = 0x1
)

const (
	SIGSTOP_IGNORED = iota /* Ignore SIGSTOP (once the parent is known).  */
	SIGSTOP_ALLOWED        /* Allow SIGSTOP (once the parent is known).   */
	SIGSTOP_PENDING        /* Block SIGSTOP until the parent is unknown.  */
)

var _ = goexec.Register("proot", NewProc)

func NewProc() (*Proot, error) {
	return &Proot{
		Rootfs: "/",
		Cmd:    nil,
	}, nil
}

func (proot *Proot) Kill() error              { return proot.Cmd.Process.Kill() }
func (proot *Proot) Signal(s os.Signal) error { return proot.Cmd.Process.Signal(s) }

func (proot *Proot) Close() error {
	if proot.Cmd.Process != nil {
		return proot.Cmd.Process.Signal(os.Interrupt)
	}

	return nil
}

func (proot *Proot) Start(options *goexec.Exec) error {
	proot.Cmd = exec.Command(options.Arguments[0], options.Arguments[1:]...)
	if err := proot.Cmd.Err; err != nil {
		return err
	}
	if proot.Cmd.SysProcAttr == nil {
		proot.Cmd.SysProcAttr = &syscall.SysProcAttr{}
	}
	proot.Cmd.SysProcAttr.Ptrace = true
	proot.Cmd.SysProcAttr.Cloneflags = syscall.CLONE_NEWUSER

	// attach stdin
	switch {
	case options.Stdin != nil:
		proot.Cmd.Stdin = options.Stdin
	case proot.Stdin != nil:
		proot.Cmd.Stdin = proot.Stdin
	}

	// attach stdout
	switch {
	case options.Stdout != nil:
		proot.Cmd.Stdout = options.Stdout
	case proot.Stdout != nil:
		proot.Cmd.Stdout = proot.Stdout
	}

	// attach stderr
	switch {
	case options.Stderr != nil:
		proot.Cmd.Stderr = options.Stderr
	case proot.Stderr != nil:
		proot.Cmd.Stderr = proot.Stderr
	}

	runtime.LockOSThread() // Lock thread to use PTRACE
	proot.done, proot.donefFn = context.WithCancel(context.Background())
	// go proot.Event() // Start background loop event

	return proot.Cmd.Start()
}