about summary refs log tree commit diff
path: root/vendor/golang.org/x/sys/unix/unveil_openbsd.go
blob: cb7e598cef9d7f67a0f2cca35ab1d831ed23577b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package unix

import "fmt"

// Unveil implements the unveil syscall.
// For more information see unveil(2).
// Note that the special case of blocking further
// unveil calls is handled by UnveilBlock.
func Unveil(path string, flags string) error {
	if err := supportsUnveil(); err != nil {
		return err
	}
	pathPtr, err := BytePtrFromString(path)
	if err != nil {
		return err
	}
	flagsPtr, err := BytePtrFromString(flags)
	if err != nil {
		return err
	}
	return unveil(pathPtr, flagsPtr)
}

// UnveilBlock blocks future unveil calls.
// For more information see unveil(2).
func UnveilBlock() error {
	if err := supportsUnveil(); err != nil {
		return err
	}
	return unveil(nil, nil)
}

// supportsUnveil checks for availability of the unveil(2) system call based
// on the running OpenBSD version.
func supportsUnveil() error {
	maj, min, err := majmin()
	if err != nil {
		return err
	}

	// unveil is not available before 6.4
	if maj < 6 || (maj == 6 && min <= 3) {
		return fmt.Errorf("cannot call Unveil on OpenBSD %d.%d", maj, min)
	}

	return nil
}