1 // Copyright 2018 The Go Authors. All rights reserved.

     2 // Use of this source code is governed by a BSD-style

     3 // license that can be found in the LICENSE file.

     4 

     5 package unix

     6 

     7 import (

     8 	"syscall"

     9 	"unsafe"

    10 )

    11 

    12 // Unveil implements the unveil syscall.

    13 // For more information see unveil(2).

    14 // Note that the special case of blocking further

    15 // unveil calls is handled by UnveilBlock.

    16 func Unveil(path string, flags string) error {

    17 	pathPtr, err := syscall.BytePtrFromString(path)

    18 	if err != nil {

    19 		return err

    20 	}

    21 	flagsPtr, err := syscall.BytePtrFromString(flags)

    22 	if err != nil {

    23 		return err

    24 	}

    25 	_, _, e := syscall.Syscall(SYS_UNVEIL, uintptr(unsafe.Pointer(pathPtr)), uintptr(unsafe.Pointer(flagsPtr)), 0)

    26 	if e != 0 {

    27 		return e

    28 	}

    29 	return nil

    30 }

    31 

    32 // UnveilBlock blocks future unveil calls.

    33 // For more information see unveil(2).

    34 func UnveilBlock() error {

    35 	// Both pointers must be nil.

    36 	var pathUnsafe, flagsUnsafe unsafe.Pointer

    37 	_, _, e := syscall.Syscall(SYS_UNVEIL, uintptr(pathUnsafe), uintptr(flagsUnsafe), 0)

    38 	if e != 0 {

    39 		return e

    40 	}

    41 	return nil

    42 }