blob: 5f63147e06c184cb02a89c3e74eff166c4cc80ee (
plain) (
blame)
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
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
|
// Copyright 2011 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.
// Socket control messages
package unix
import "unsafe"
// UnixCredentials encodes credentials into a socket control message
// for sending to another process. This can be used for
// authentication.
func UnixCredentials(ucred *Ucred) []byte {
b := make([]byte, CmsgSpace(SizeofUcred))
h := (*Cmsghdr)(unsafe.Pointer(&b[0]))
h.Level = SOL_SOCKET
h.Type = SCM_CREDENTIALS
h.SetLen(CmsgLen(SizeofUcred))
*(*Ucred)(h.data(0)) = *ucred
return b
}
// ParseUnixCredentials decodes a socket control message that contains
// credentials in a Ucred structure. To receive such a message, the
// SO_PASSCRED option must be enabled on the socket.
func ParseUnixCredentials(m *SocketControlMessage) (*Ucred, error) {
if m.Header.Level != SOL_SOCKET {
return nil, EINVAL
}
if m.Header.Type != SCM_CREDENTIALS {
return nil, EINVAL
}
ucred := *(*Ucred)(unsafe.Pointer(&m.Data[0]))
return &ucred, nil
}
// PktInfo4 encodes Inet4Pktinfo into a socket control message of type IP_PKTINFO.
func PktInfo4(info *Inet4Pktinfo) []byte {
b := make([]byte, CmsgSpace(SizeofInet4Pktinfo))
h := (*Cmsghdr)(unsafe.Pointer(&b[0]))
h.Level = SOL_IP
h.Type = IP_PKTINFO
h.SetLen(CmsgLen(SizeofInet4Pktinfo))
*(*Inet4Pktinfo)(h.data(0)) = *info
return b
}
// PktInfo6 encodes Inet6Pktinfo into a socket control message of type IPV6_PKTINFO.
func PktInfo6(info *Inet6Pktinfo) []byte {
b := make([]byte, CmsgSpace(SizeofInet6Pktinfo))
h := (*Cmsghdr)(unsafe.Pointer(&b[0]))
h.Level = SOL_IPV6
h.Type = IPV6_PKTINFO
h.SetLen(CmsgLen(SizeofInet6Pktinfo))
*(*Inet6Pktinfo)(h.data(0)) = *info
return b
}
// ParseOrigDstAddr decodes a socket control message containing the original
// destination address. To receive such a message the IP_RECVORIGDSTADDR or
// IPV6_RECVORIGDSTADDR option must be enabled on the socket.
func ParseOrigDstAddr(m *SocketControlMessage) (Sockaddr, error) {
switch {
case m.Header.Level == SOL_IP && m.Header.Type == IP_ORIGDSTADDR:
pp := (*RawSockaddrInet4)(unsafe.Pointer(&m.Data[0]))
sa := new(SockaddrInet4)
p := (*[2]byte)(unsafe.Pointer(&pp.Port))
sa.Port = int(p[0])<<8 + int(p[1])
sa.Addr = pp.Addr
return sa, nil
case m.Header.Level == SOL_IPV6 && m.Header.Type == IPV6_ORIGDSTADDR:
pp := (*RawSockaddrInet6)(unsafe.Pointer(&m.Data[0]))
sa := new(SockaddrInet6)
p := (*[2]byte)(unsafe.Pointer(&pp.Port))
sa.Port = int(p[0])<<8 + int(p[1])
sa.ZoneId = pp.Scope_id
sa.Addr = pp.Addr
return sa, nil
default:
return nil, EINVAL
}
}
|
