1 // Copyright 2011 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 // Socket control messages 6 7 package syscall 8 9 import "unsafe" 10 11 // UnixCredentials encodes credentials into a socket control message 12 // for sending to another process. This can be used for 13 // authentication. 14 func UnixCredentials(ucred *Ucred) []byte { 15 b := make([]byte, CmsgSpace(SizeofUcred)) 16 h := (*Cmsghdr)(unsafe.Pointer(&b[0])) 17 h.Level = SOL_SOCKET 18 h.Type = SCM_CREDENTIALS 19 h.SetLen(CmsgLen(SizeofUcred)) 20 *((*Ucred)(cmsgData(h))) = *ucred 21 return b 22 } 23 24 // ParseUnixCredentials decodes a socket control message that contains 25 // credentials in a Ucred structure. To receive such a message, the 26 // SO_PASSCRED option must be enabled on the socket. 27 func ParseUnixCredentials(m *SocketControlMessage) (*Ucred, error) { 28 if m.Header.Level != SOL_SOCKET { 29 return nil, EINVAL 30 } 31 if m.Header.Type != SCM_CREDENTIALS { 32 return nil, EINVAL 33 } 34 if uintptr(len(m.Data)) < unsafe.Sizeof(Ucred{}) { 35 return nil, EINVAL 36 } 37 ucred := *(*Ucred)(unsafe.Pointer(&m.Data[0])) 38 return &ucred, nil 39 } 40
