mirror of
https://github.com/golang/go
synced 2024-11-25 01:27:56 -07:00
syscall: Parse and encode SCM_RIGHTS and SCM_CREDENTIALS.
R=rsc, agl, mikioh.mikioh CC=golang-dev https://golang.org/cl/4667066
This commit is contained in:
parent
c1f035ba4c
commit
870fdd760a
@ -36,6 +36,7 @@ GOFILES_linux=\
|
|||||||
exec_unix.go\
|
exec_unix.go\
|
||||||
lsf_linux.go\
|
lsf_linux.go\
|
||||||
netlink_linux.go\
|
netlink_linux.go\
|
||||||
|
sockcmsg_linux.go\
|
||||||
sockcmsg_unix.go\
|
sockcmsg_unix.go\
|
||||||
syscall_unix.go\
|
syscall_unix.go\
|
||||||
|
|
||||||
|
38
src/pkg/syscall/sockcmsg_linux.go
Normal file
38
src/pkg/syscall/sockcmsg_linux.go
Normal file
@ -0,0 +1,38 @@
|
|||||||
|
// 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 syscall
|
||||||
|
|
||||||
|
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 {
|
||||||
|
buf := make([]byte, CmsgSpace(SizeofUcred))
|
||||||
|
cmsg := (*Cmsghdr)(unsafe.Pointer(&buf[0]))
|
||||||
|
cmsg.Level = SOL_SOCKET
|
||||||
|
cmsg.Type = SCM_CREDENTIALS
|
||||||
|
cmsg.SetLen(CmsgLen(SizeofUcred))
|
||||||
|
*((*Ucred)(cmsgData(cmsg))) = *ucred
|
||||||
|
return buf
|
||||||
|
}
|
||||||
|
|
||||||
|
// 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(msg *SocketControlMessage) (*Ucred, int) {
|
||||||
|
if msg.Header.Level != SOL_SOCKET {
|
||||||
|
return nil, EINVAL
|
||||||
|
}
|
||||||
|
if msg.Header.Type != SCM_CREDENTIALS {
|
||||||
|
return nil, EINVAL
|
||||||
|
}
|
||||||
|
ucred := *(*Ucred)(unsafe.Pointer(&msg.Data[0]))
|
||||||
|
return &ucred, 0
|
||||||
|
}
|
@ -24,10 +24,22 @@ func cmsgAlignOf(salen int) int {
|
|||||||
return (salen + salign - 1) & ^(salign - 1)
|
return (salen + salign - 1) & ^(salign - 1)
|
||||||
}
|
}
|
||||||
|
|
||||||
func cmsgLen(datalen int) int {
|
// CmsgLen returns the value to store in the Len field of the Cmsghdr
|
||||||
|
// structure, taking into account any necessary alignment.
|
||||||
|
func CmsgLen(datalen int) int {
|
||||||
return cmsgAlignOf(SizeofCmsghdr) + datalen
|
return cmsgAlignOf(SizeofCmsghdr) + datalen
|
||||||
}
|
}
|
||||||
|
|
||||||
|
// CmsgSpace returns the number of bytes an ancillary element with
|
||||||
|
// payload of the passed data length occupies.
|
||||||
|
func CmsgSpace(datalen int) int {
|
||||||
|
return cmsgAlignOf(SizeofCmsghdr) + cmsgAlignOf(datalen)
|
||||||
|
}
|
||||||
|
|
||||||
|
func cmsgData(cmsg *Cmsghdr) unsafe.Pointer {
|
||||||
|
return unsafe.Pointer(uintptr(unsafe.Pointer(cmsg)) + SizeofCmsghdr)
|
||||||
|
}
|
||||||
|
|
||||||
type SocketControlMessage struct {
|
type SocketControlMessage struct {
|
||||||
Header Cmsghdr
|
Header Cmsghdr
|
||||||
Data []byte
|
Data []byte
|
||||||
@ -41,7 +53,7 @@ func ParseSocketControlMessage(buf []byte) ([]SocketControlMessage, int) {
|
|||||||
cmsgs []SocketControlMessage
|
cmsgs []SocketControlMessage
|
||||||
)
|
)
|
||||||
|
|
||||||
for len(buf) >= cmsgLen(0) {
|
for len(buf) >= CmsgLen(0) {
|
||||||
h, dbuf, e = socketControlMessageHeaderAndData(buf)
|
h, dbuf, e = socketControlMessageHeaderAndData(buf)
|
||||||
if e != 0 {
|
if e != 0 {
|
||||||
break
|
break
|
||||||
@ -63,3 +75,39 @@ func socketControlMessageHeaderAndData(buf []byte) (*Cmsghdr, []byte, int) {
|
|||||||
}
|
}
|
||||||
return h, buf[cmsgAlignOf(SizeofCmsghdr):], 0
|
return h, buf[cmsgAlignOf(SizeofCmsghdr):], 0
|
||||||
}
|
}
|
||||||
|
|
||||||
|
// UnixRights encodes a set of open file descriptors into a socket
|
||||||
|
// control message for sending to another process.
|
||||||
|
func UnixRights(fds ...int) []byte {
|
||||||
|
datalen := len(fds) * 4
|
||||||
|
buf := make([]byte, CmsgSpace(datalen))
|
||||||
|
cmsg := (*Cmsghdr)(unsafe.Pointer(&buf[0]))
|
||||||
|
cmsg.Level = SOL_SOCKET
|
||||||
|
cmsg.Type = SCM_RIGHTS
|
||||||
|
cmsg.SetLen(CmsgLen(datalen))
|
||||||
|
|
||||||
|
data := uintptr(cmsgData(cmsg))
|
||||||
|
for _, fd := range fds {
|
||||||
|
*(*int32)(unsafe.Pointer(data)) = int32(fd)
|
||||||
|
data += 4
|
||||||
|
}
|
||||||
|
|
||||||
|
return buf
|
||||||
|
}
|
||||||
|
|
||||||
|
// ParseUnixRights decodes a socket control message that contains an
|
||||||
|
// integer array of open file descriptors from another process.
|
||||||
|
func ParseUnixRights(msg *SocketControlMessage) ([]int, int) {
|
||||||
|
if msg.Header.Level != SOL_SOCKET {
|
||||||
|
return nil, EINVAL
|
||||||
|
}
|
||||||
|
if msg.Header.Type != SCM_RIGHTS {
|
||||||
|
return nil, EINVAL
|
||||||
|
}
|
||||||
|
fds := make([]int, len(msg.Data)>>2)
|
||||||
|
for i, j := 0, 0; i < len(msg.Data); i += 4 {
|
||||||
|
fds[j] = int(*(*int32)(unsafe.Pointer(&msg.Data[i])))
|
||||||
|
j++
|
||||||
|
}
|
||||||
|
return fds, 0
|
||||||
|
}
|
||||||
|
Loading…
Reference in New Issue
Block a user