// Copyright 2009 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.
// Linux system calls.
// This file is compiled as ordinary Go code,
// but it is also input to mksyscall,
// which parses the //sys lines and generates system call stubs.
// Note that sometimes we use a lowercase //sys name and
// wrap it in our own nicer implementation.
package unix
import (
"encoding/binary"
"runtime"
"syscall"
"unsafe"
)
/*
* Wrapped
*/
func Access(path string, mode uint32) (err error) {
return Faccessat(AT_FDCWD, path, mode, 0)
}
func Chmod(path string, mode uint32) (err error) {
return Fchmodat(AT_FDCWD, path, mode, 0)
}
func Chown(path string, uid int, gid int) (err error) {
return Fchownat(AT_FDCWD, path, uid, gid, 0)
}
func Creat(path string, mode uint32) (fd int, err error) {
return Open(path, O_CREAT|O_WRONLY|O_TRUNC, mode)
}
//sys FanotifyInit(flags uint, event_f_flags uint) (fd int, err error)
//sys fanotifyMark(fd int, flags uint, mask uint64, dirFd int, pathname *byte) (err error)
func FanotifyMark(fd int, flags uint, mask uint64, dirFd int, pathname string) (err error) {
if pathname == "" {
return fanotifyMark(fd, flags, mask, dirFd, nil)
}
p, err := BytePtrFromString(pathname)
if err != nil {
return err
}
return fanotifyMark(fd, flags, mask, dirFd, p)
}
//sys fchmodat(dirfd int, path string, mode uint32) (err error)
func Fchmodat(dirfd int, path string, mode uint32, flags int) (err error) {
// Linux fchmodat doesn't support the flags parameter. Mimick glibc's behavior
// and check the flags. Otherwise the mode would be applied to the symlink
// destination which is not what the user expects.
if flags&^AT_SYMLINK_NOFOLLOW != 0 {
return EINVAL
} else if flags&AT_SYMLINK_NOFOLLOW != 0 {
return EOPNOTSUPP
}
return fchmodat(dirfd, path, mode)
}
//sys ioctl(fd int, req uint, arg uintptr) (err error)
// ioctl itself should not be exposed directly, but additional get/set
// functions for specific types are permissible.
// IoctlRetInt performs an ioctl operation specified by req on a device
// associated with opened file descriptor fd, and returns a non-negative
// integer that is returned by the ioctl syscall.
func IoctlRetInt(fd int, req uint) (int, error) {
ret, _, err := Syscall(SYS_IOCTL, uintptr(fd), uintptr(req), 0)
if err != 0 {
return 0, err
}
return int(ret), nil
}
func IoctlSetRTCTime(fd int, value *RTCTime) error {
err := ioctl(fd, RTC_SET_TIME, uintptr(unsafe.Pointer(value)))
runtime.KeepAlive(value)
return err
}
func IoctlSetRTCWkAlrm(fd int, value *RTCWkAlrm) error {
err := ioctl(fd, RTC_WKALM_SET, uintptr(unsafe.Pointer(value)))
runtime.KeepAlive(value)
return err
}
func IoctlGetUint32(fd int, req uint) (uint32, error) {
var value uint32
err := ioctl(fd, req, uintptr(unsafe.Pointer(&value)))
return value, err
}
func IoctlGetRTCTime(fd int) (*RTCTime, error) {
var value RTCTime
err := ioctl(fd, RTC_RD_TIME, uintptr(unsafe.Pointer(&value)))
return &value, err
}
func IoctlGetRTCWkAlrm(fd int) (*RTCWkAlrm, error) {
var value RTCWkAlrm
err := ioctl(fd, RTC_WKALM_RD, uintptr(unsafe.Pointer(&value)))
return &value, err
}
//sys Linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error)
func Link(oldpath string, newpath string) (err error) {
return Linkat(AT_FDCWD, oldpath, AT_FDCWD, newpath, 0)
}
func Mkdir(path string, mode uint32) (err error) {
return Mkdirat(AT_FDCWD, path, mode)
}
func Mknod(path string, mode uint32, dev int) (err error) {
return Mknodat(AT_FDCWD, path, mode, dev)
}
func Open(path string, mode int, perm uint32) (fd int, err error) {
return openat(AT_FDCWD, path, mode|O_LARGEFILE, perm)
}
//sys openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) {
return openat(dirfd, path, flags|O_LARGEFILE, mode)
}
//sys ppoll(fds *PollFd, nfds int, timeout *Timespec, sigmask *Sigset_t) (n int, err error)
func Ppoll(fds []PollFd, timeout *Timespec, sigmask *Sigset_t) (n int, err error) {
if len(fds) == 0 {
return ppoll(nil, 0, timeout, sigmask)
}
return ppoll(&fds[0], len(fds), timeout, sigmask)
}
//sys Readlinkat(dirfd int, path string, buf []byte) (n int, err error)
func Readlink(path string, buf []byte) (n int, err error) {
return Readlinkat(AT_FDCWD, path, buf)
}
func Rename(oldpath string, newpath string) (err error) {
return Renameat(AT_FDCWD, oldpath, AT_FDCWD, newpath)
}
func Rmdir(path string) error {
return Unlinkat(AT_FDCWD, path, AT_REMOVEDIR)
}
//sys Symlinkat(oldpath string, newdirfd int, newpath string) (err error)
func Symlink(oldpath string, newpath string) (err error) {
return Symlinkat(oldpath, AT_FDCWD, newpath)
}
func Unlink(path string) error {
return Unlinkat(AT_FDCWD, path, 0)
}
//sys Unlinkat(dirfd int, path string, flags int) (err error)
func Utimes(path string, tv []Timeval) error {
if tv == nil {
err := utimensat(AT_FDCWD, path, nil, 0)
if err != ENOSYS {
return err
}
return utimes(path, nil)
}
if len(tv) != 2 {
return EINVAL
}
var ts [2]Timespec
ts[0] = NsecToTimespec(TimevalToNsec(tv[0]))
ts[1] = NsecToTimespec(TimevalToNsec(tv[1]))
err := utimensat(AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
if err != ENOSYS {
return err
}
return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
}
//sys utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error)
func UtimesNano(path string, ts []Timespec) error {
if ts == nil {
err := utimensat(AT_FDCWD, path, nil, 0)
if err != ENOSYS {
return err
}
return utimes(path, nil)
}
if len(ts) != 2 {
return EINVAL
}
err := utimensat(AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
if err != ENOSYS {
return err
}
// If the utimensat syscall isn't available (utimensat was added to Linux
// in 2.6.22, Released, 8 July 2007) then fall back to utimes
var tv [2]Timeval
for i := 0; i < 2; i++ {
tv[i] = NsecToTimeval(TimespecToNsec(ts[i]))
}
return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
}
func UtimesNanoAt(dirfd int, path string, ts []Timespec, flags int) error {
if ts == nil {
return utimensat(dirfd, path, nil, flags)
}
if len(ts) != 2 {
return EINVAL
}
return utimensat(dirfd, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), flags)
}
func Futimesat(dirfd int, path string, tv []Timeval) error {
if tv == nil {
return futimesat(dirfd, path, nil)
}
if len(tv) != 2 {
return EINVAL
}
return futimesat(dirfd, path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
}
func Futimes(fd int, tv []Timeval) (err error) {
// Believe it or not, this is the best we can do on Linux
// (and is what glibc does).
return Utimes("/proc/self/fd/"+itoa(fd), tv)
}
const ImplementsGetwd = true
//sys Getcwd(buf []byte) (n int, err error)
func Getwd() (wd string, err error) {
var buf [PathMax]byte
n, err := Getcwd(buf[0:])
if err != nil {
return "", err
}
// Getcwd returns the number of bytes written to buf, including the NUL.
if n < 1 || n > len(buf) || buf[n-1] != 0 {
return "", EINVAL
}
return string(buf[0 : n-1]), nil
}
func Getgroups() (gids []int, err error) {
n, err := getgroups(0, nil)
if err != nil {
return nil, err
}
if n == 0 {
return nil, nil
}
// Sanity check group count. Max is 1<<16 on Linux.
if n < 0 || n > 1<<20 {
return nil, EINVAL
}
a := make([]_Gid_t, n)
n, err = getgroups(n, &a[0])
if err != nil {
return nil, err
}
gids = make([]int, n)
for i, v := range a[0:n] {
gids[i] = int(v)
}
return
}
func Setgroups(gids []int) (err error) {
if len(gids) == 0 {
return setgroups(0, nil)
}
a := make([]_Gid_t, len(gids))
for i, v := range gids {
a[i] = _Gid_t(v)
}
return setgroups(len(a), &a[0])
}
type WaitStatus uint32
// Wait status is 7 bits at bottom, either 0 (exited),
// 0x7F (stopped), or a signal number that caused an exit.
// The 0x80 bit is whether there was a core dump.
// An extra number (exit code, signal causing a stop)
// is in the high bits. At least that's the idea.
// There are various irregularities. For example, the
// "continued" status is 0xFFFF, distinguishing itself
// from stopped via the core dump bit.
const (
mask = 0x7F
core = 0x80
exited = 0x00
stopped = 0x7F
shift = 8
)
func (w WaitStatus) Exited() bool { return w&mask == exited }
func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != exited }
func (w WaitStatus) Stopped() bool { return w&0xFF == stopped }
func (w WaitStatus) Continued() bool { return w == 0xFFFF }
func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 }
func (w WaitStatus) ExitStatus() int {
if !w.Exited() {
return -1
}
return int(w>>shift) & 0xFF
}
func (w WaitStatus) Signal() syscall.Signal {
if !w.Signaled() {
return -1
}
return syscall.Signal(w & mask)
}
func (w WaitStatus) StopSignal() syscall.Signal {
if !w.Stopped() {
return -1
}
return syscall.Signal(w>>shift) & 0xFF
}
func (w WaitStatus) TrapCause() int {
if w.StopSignal() != SIGTRAP {
return -1
}
return int(w>>shift) >> 8
}
//sys wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error)
func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) {
var status _C_int
wpid, err = wait4(pid, &status, options, rusage)
if wstatus != nil {
*wstatus = WaitStatus(status)
}
return
}
func Mkfifo(path string, mode uint32) error {
return Mknod(path, mode|S_IFIFO, 0)
}
func Mkfifoat(dirfd int, path string, mode uint32) error {
return Mknodat(dirfd, path, mode|S_IFIFO, 0)
}
func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
if sa.Port < 0 || sa.Port > 0xFFFF {
return nil, 0, EINVAL
}
sa.raw.Family = AF_INET
p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
p[0] = byte(sa.Port >> 8)
p[1] = byte(sa.Port)
for i := 0; i < len(sa.Addr); i++ {
sa.raw.Addr[i] = sa.Addr[i]
}
return unsafe.Pointer(&sa.raw), SizeofSockaddrInet4, nil
}
func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) {
if sa.Port < 0 || sa.Port > 0xFFFF {
return nil, 0, EINVAL
}
sa.raw.Family = AF_INET6
p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
p[0] = byte(sa.Port >> 8)
p[1] = byte(sa.Port)
sa.raw.Scope_id = sa.ZoneId
for i := 0; i < len(sa.Addr); i++ {
sa.raw.Addr[i] = sa.Addr[i]
}
return unsafe.Pointer(&sa.raw), SizeofSockaddrInet6, nil
}
func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) {
name := sa.Name
n := len(name)
if n >= len(sa.raw.Path) {
return nil, 0, EINVAL
}
sa.raw.Family = AF_UNIX
for i := 0; i < n; i++ {
sa.raw.Path[i] = int8(name[i])
}
// length is family (uint16), name, NUL.
sl := _Socklen(2)
if n > 0 {
sl += _Socklen(n) + 1
}
if sa.raw.Path[0] == '@' {
sa.raw.Path[0] = 0
// Don't count trailing NUL for abstract address.
sl--
}
return unsafe.Pointer(&sa.raw), sl, nil
}
// SockaddrLinklayer implements the Sockaddr interface for AF_PACKET type sockets.
type SockaddrLinklayer struct {
Protocol uint16
Ifindex int
Hatype uint16
Pkttype uint8
Halen uint8
Addr [8]byte
raw RawSockaddrLinklayer
}
func (sa *SockaddrLinklayer) sockaddr() (unsafe.Pointer, _Socklen, error) {
if sa.Ifindex < 0 || sa.Ifindex > 0x7fffffff {
return nil, 0, EINVAL
}
sa.raw.Family = AF_PACKET
sa.raw.Protocol = sa.Protocol
sa.raw.Ifindex = int32(sa.Ifindex)
sa.raw.Hatype = sa.Hatype
sa.raw.Pkttype = sa.Pkttype
sa.raw.Halen = sa.Halen
for i := 0; i < len(sa.Addr); i++ {
sa.raw.Addr[i] = sa.Addr[i]
}
return unsafe.Pointer(&sa.raw), SizeofSockaddrLinklayer, nil
}
// SockaddrNetlink implements the Sockaddr interface for AF_NETLINK type sockets.
type SockaddrNetlink struct {
Family uint16
Pad uint16
Pid uint32
Groups uint32
raw RawSockaddrNetlink
}
func (sa *SockaddrNetlink) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_NETLINK
sa.raw.Pad = sa.Pad
sa.raw.Pid = sa.Pid
sa.raw.Groups = sa.Groups
return unsafe.Pointer(&sa.raw), SizeofSockaddrNetlink, nil
}
// SockaddrHCI implements the Sockaddr interface for AF_BLUETOOTH type sockets
// using the HCI protocol.
type SockaddrHCI struct {
Dev uint16
Channel uint16
raw RawSockaddrHCI
}
func (sa *SockaddrHCI) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_BLUETOOTH
sa.raw.Dev = sa.Dev
sa.raw.Channel = sa.Channel
return unsafe.Pointer(&sa.raw), SizeofSockaddrHCI, nil
}
// SockaddrL2 implements the Sockaddr interface for AF_BLUETOOTH type sockets
// using the L2CAP protocol.
type SockaddrL2 struct {
PSM uint16
CID uint16
Addr [6]uint8
AddrType uint8
raw RawSockaddrL2
}
func (sa *SockaddrL2) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_BLUETOOTH
psm := (*[2]byte)(unsafe.Pointer(&sa.raw.Psm))
psm[0] = byte(sa.PSM)
psm[1] = byte(sa.PSM >> 8)
for i := 0; i < len(sa.Addr); i++ {
sa.raw.Bdaddr[i] = sa.Addr[len(sa.Addr)-1-i]
}
cid := (*[2]byte)(unsafe.Pointer(&sa.raw.Cid))
cid[0] = byte(sa.CID)
cid[1] = byte(sa.CID >> 8)
sa.raw.Bdaddr_type = sa.AddrType
return unsafe.Pointer(&sa.raw), SizeofSockaddrL2, nil
}
// SockaddrRFCOMM implements the Sockaddr interface for AF_BLUETOOTH type sockets
// using the RFCOMM protocol.
//
// Server example:
//
// fd, _ := Socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM)
// _ = unix.Bind(fd, &unix.SockaddrRFCOMM{
// Channel: 1,
// Addr: [6]uint8{0, 0, 0, 0, 0, 0}, // BDADDR_ANY or 00:00:00:00:00:00
// })
// _ = Listen(fd, 1)
// nfd, sa, _ := Accept(fd)
// fmt.Printf("conn addr=%v fd=%d", sa.(*unix.SockaddrRFCOMM).Addr, nfd)
// Read(nfd, buf)
//
// Client example:
//
// fd, _ := Socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM)
// _ = Connect(fd, &SockaddrRFCOMM{
// Channel: 1,
// Addr: [6]byte{0x11, 0x22, 0x33, 0xaa, 0xbb, 0xcc}, // CC:BB:AA:33:22:11
// })
// Write(fd, []byte(`hello`))
type SockaddrRFCOMM struct {
// Addr represents a bluetooth address, byte ordering is little-endian.
Addr [6]uint8
// Channel is a designated bluetooth channel, only 1-30 are available for use.
// Since Linux 2.6.7 and further zero value is the first available channel.
Channel uint8
raw RawSockaddrRFCOMM
}
func (sa *SockaddrRFCOMM) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_BLUETOOTH
sa.raw.Channel = sa.Channel
sa.raw.Bdaddr = sa.Addr
return unsafe.Pointer(&sa.raw), SizeofSockaddrRFCOMM, nil
}
// SockaddrCAN implements the Sockaddr interface for AF_CAN type sockets.
// The RxID and TxID fields are used for transport protocol addressing in
// (CAN_TP16, CAN_TP20, CAN_MCNET, and CAN_ISOTP), they can be left with
// zero values for CAN_RAW and CAN_BCM sockets as they have no meaning.
//
// The SockaddrCAN struct must be bound to the socket file descriptor
// using Bind before the CAN socket can be used.
//
// // Read one raw CAN frame
// fd, _ := Socket(AF_CAN, SOCK_RAW, CAN_RAW)
// addr := &SockaddrCAN{Ifindex: index}
// Bind(fd, addr)
// frame := make([]byte, 16)
// Read(fd, frame)
//
// The full SocketCAN documentation can be found in the linux kernel
// archives at: https://www.kernel.org/doc/Documentation/networking/can.txt
type SockaddrCAN struct {
Ifindex int
RxID uint32
TxID uint32
raw RawSockaddrCAN
}
func (sa *SockaddrCAN) sockaddr() (unsafe.Pointer, _Socklen, error) {
if sa.Ifindex < 0 || sa.Ifindex > 0x7fffffff {
return nil, 0, EINVAL
}
sa.raw.Family = AF_CAN
sa.raw.Ifindex = int32(sa.Ifindex)
rx := (*[4]byte)(unsafe.Pointer(&sa.RxID))
for i := 0; i < 4; i++ {
sa.raw.Addr[i] = rx[i]
}
tx := (*[4]byte)(unsafe.Pointer(&sa.TxID))
for i := 0; i < 4; i++ {
sa.raw.Addr[i+4] = tx[i]
}
return unsafe.Pointer(&sa.raw), SizeofSockaddrCAN, nil
}
// SockaddrALG implements the Sockaddr interface for AF_ALG type sockets.
// SockaddrALG enables userspace access to the Linux kernel's cryptography
// subsystem. The Type and Name fields specify which type of hash or cipher
// should be used with a given socket.
//
// To create a file descriptor that provides access to a hash or cipher, both
// Bind and Accept must be used. Once the setup process is complete, input
// data can be written to the socket, processed by the kernel, and then read
// back as hash output or ciphertext.
//
// Here is an example of using an AF_ALG socket with SHA1 hashing.
// The initial socket setup process is as follows:
//
// // Open a socket to perform SHA1 hashing.
// fd, _ := unix.Socket(unix.AF_ALG, unix.SOCK_SEQPACKET, 0)
// addr := &unix.SockaddrALG{Type: "hash", Name: "sha1"}
// unix.Bind(fd, addr)
// // Note: unix.Accept does not work at this time; must invoke accept()
// // manually using unix.Syscall.
// hashfd, _, _ := unix.Syscall(unix.SYS_ACCEPT, uintptr(fd), 0, 0)
//
// Once a file descriptor has been returned from Accept, it may be used to
// perform SHA1 hashing. The descriptor is not safe for concurrent use, but
// may be re-used repeatedly with subsequent Write and Read operations.
//
// When hashing a small byte slice or string, a single Write and Read may
// be used:
//
// // Assume hashfd is already configured using the setup process.
// hash := os.NewFile(hashfd, "sha1")
// // Hash an input string and read the results. Each Write discards
// // previous hash state. Read always reads the current state.
// b := make([]byte, 20)
// for i := 0; i < 2; i++ {
// io.WriteString(hash, "Hello, world.")
// hash.Read(b)
// fmt.Println(hex.EncodeToString(b))
// }
// // Output:
// // 2ae01472317d1935a84797ec1983ae243fc6aa28
// // 2ae01472317d1935a84797ec1983ae243fc6aa28
//
// For hashing larger byte slices, or byte streams such as those read from
// a file or socket, use Sendto with MSG_MORE to instruct the kernel to update
// the hash digest instead of creating a new one for a given chunk and finalizing it.
//
// // Assume hashfd and addr are already configured using the setup process.
// hash := os.NewFile(hashfd, "sha1")
// // Hash the contents of a file.
// f, _ := os.Open("/tmp/linux-4.10-rc7.tar.xz")
// b := make([]byte, 4096)
// for {
// n, err := f.Read(b)
// if err == io.EOF {
// break
// }
// unix.Sendto(hashfd, b[:n], unix.MSG_MORE, addr)
// }
// hash.Read(b)
// fmt.Println(hex.EncodeToString(b))
// // Output: 85cdcad0c06eef66f805ecce353bec9accbeecc5
//
// For more information, see: http://www.chronox.de/crypto-API/crypto/userspace-if.html.
type SockaddrALG struct {
Type string
Name string
Feature uint32
Mask uint32
raw RawSockaddrALG
}
func (sa *SockaddrALG) sockaddr() (unsafe.Pointer, _Socklen, error) {
// Leave room for NUL byte terminator.
if len(sa.Type) > 13 {
return nil, 0, EINVAL
}
if len(sa.Name) > 63 {
return nil, 0, EINVAL
}
sa.raw.Family = AF_ALG
sa.raw.Feat = sa.Feature
sa.raw.Mask = sa.Mask
typ, err := ByteSliceFromString(sa.Type)
if err != nil {
return nil, 0, err
}
name, err := ByteSliceFromString(sa.Name)
if err != nil {
return nil, 0, err
}
copy(sa.raw.Type[:], typ)
copy(sa.raw.Name[:], name)
return unsafe.Pointer(&sa.raw), SizeofSockaddrALG, nil
}
// SockaddrVM implements the Sockaddr interface for AF_VSOCK type sockets.
// SockaddrVM provides access to Linux VM sockets: a mechanism that enables
// bidirectional communication between a hypervisor and its guest virtual
// machines.
type SockaddrVM struct {
// CID and Port specify a context ID and port address for a VM socket.
// Guests have a unique CID, and hosts may have a well-known CID of:
// - VMADDR_CID_HYPERVISOR: refers to the hypervisor process.
// - VMADDR_CID_HOST: refers to other processes on the host.
CID uint32
Port uint32
raw RawSockaddrVM
}
func (sa *SockaddrVM) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_VSOCK
sa.raw.Port = sa.Port
sa.raw.Cid = sa.CID
return unsafe.Pointer(&sa.raw), SizeofSockaddrVM, nil
}
type SockaddrXDP struct {
Flags uint16
Ifindex uint32
QueueID uint32
SharedUmemFD uint32
raw RawSockaddrXDP
}
func (sa *SockaddrXDP) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_XDP
sa.raw.Flags = sa.Flags
sa.raw.Ifindex = sa.Ifindex
sa.raw.Queue_id = sa.QueueID
sa.raw.Shared_umem_fd = sa.SharedUmemFD
return unsafe.Pointer(&sa.raw), SizeofSockaddrXDP, nil
}
// This constant mirrors the #define of PX_PROTO_OE in
// linux/if_pppox.h. We're defining this by hand here instead of
// autogenerating through mkerrors.sh because including
// linux/if_pppox.h causes some declaration conflicts with other
// includes (linux/if_pppox.h includes linux/in.h, which conflicts
// with netinet/in.h). Given that we only need a single zero constant
// out of that file, it's cleaner to just define it by hand here.
const px_proto_oe = 0
type SockaddrPPPoE struct {
SID uint16
Remote []byte
Dev string
raw RawSockaddrPPPoX
}
func (sa *SockaddrPPPoE) sockaddr() (unsafe.Pointer, _Socklen, error) {
if len(sa.Remote) != 6 {
return nil, 0, EINVAL
}
if len(sa.Dev) > IFNAMSIZ-1 {
return nil, 0, EINVAL
}
*(*uint16)(unsafe.Pointer(&sa.raw[0])) = AF_PPPOX
// This next field is in host-endian byte order. We can't use the
// same unsafe pointer cast as above, because this value is not
// 32-bit aligned and some architectures don't allow unaligned
// access.
//
// However, the value of px_proto_oe is 0, so we can use
// encoding/binary helpers to write the bytes without worrying
// about the ordering.
binary.BigEndian.PutUint32(sa.raw[2:6], px_proto_oe)
// This field is deliberately big-endian, unlike the previous
// one. The kernel expects SID to be in network byte order.
binary.BigEndian.PutUint16(sa.raw[6:8], sa.SID)
copy(sa.raw[8:14], sa.Remote)
for i := 14; i < 14+IFNAMSIZ; i++ {
sa.raw[i] = 0
}
copy(sa.raw[14:], sa.Dev)
return unsafe.Pointer(&sa.raw), SizeofSockaddrPPPoX, nil
}
// SockaddrTIPC implements the Sockaddr interface for AF_TIPC type sockets.
// For more information on TIPC, see: http://tipc.sourceforge.net/.
type SockaddrTIPC struct {
// Scope is the publication scopes when binding service/service range.
// Should be set to TIPC_CLUSTER_SCOPE or TIPC_NODE_SCOPE.
Scope int
// Addr is the type of address used to manipulate a socket. Addr must be
// one of:
// - *TIPCSocketAddr: "id" variant in the C addr union
// - *TIPCServiceRange: "nameseq" variant in the C addr union
// - *TIPCServiceName: "name" variant in the C addr union
//
// If nil, EINVAL will be returned when the structure is used.
Addr TIPCAddr
raw RawSockaddrTIPC
}
// TIPCAddr is implemented by types that can be used as an address for
// SockaddrTIPC. It is only implemented by *TIPCSocketAddr, *TIPCServiceRange,
// and *TIPCServiceName.
type TIPCAddr interface {
tipcAddrtype() uint8
tipcAddr() [12]byte
}
func (sa *TIPCSocketAddr) tipcAddr() [12]byte {
var out [12]byte
copy(out[:], (*(*[unsafe.Sizeof(TIPCSocketAddr{})]byte)(unsafe.Pointer(sa)))[:])
return out
}
func (sa *TIPCSocketAddr) tipcAddrtype() uint8 { return TIPC_SOCKET_ADDR }
func (sa *TIPCServiceRange) tipcAddr() [12]byte {
var out [12]byte
copy(out[:], (*(*[unsafe.Sizeof(TIPCServiceRange{})]byte)(unsafe.Pointer(sa)))[:])
return out
}
func (sa *TIPCServiceRange) tipcAddrtype() uint8 { return TIPC_SERVICE_RANGE }
func (sa *TIPCServiceName) tipcAddr() [12]byte {
var out [12]byte
copy(out[:], (*(*[unsafe.Sizeof(TIPCServiceName{})]byte)(unsafe.Pointer(sa)))[:])
return out
}
func (sa *TIPCServiceName) tipcAddrtype() uint8 { return TIPC_SERVICE_ADDR }
func (sa *SockaddrTIPC) sockaddr() (unsafe.Pointer, _Socklen, error) {
if sa.Addr == nil {
return nil, 0, EINVAL
}
sa.raw.Family = AF_TIPC
sa.raw.Scope = int8(sa.Scope)
sa.raw.Addrtype = sa.Addr.tipcAddrtype()
sa.raw.Addr = sa.Addr.tipcAddr()
return unsafe.Pointer(&sa.raw), SizeofSockaddrTIPC, nil
}
// SockaddrL2TPIP implements the Sockaddr interface for IPPROTO_L2TP/AF_INET sockets.
type SockaddrL2TPIP struct {
Addr [4]byte
ConnId uint32
raw RawSockaddrL2TPIP
}
func (sa *SockaddrL2TPIP) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_INET
sa.raw.Conn_id = sa.ConnId
for i := 0; i < len(sa.Addr); i++ {
sa.raw.Addr[i] = sa.Addr[i]
}
return unsafe.Pointer(&sa.raw), SizeofSockaddrL2TPIP, nil
}
// SockaddrL2TPIP6 implements the Sockaddr interface for IPPROTO_L2TP/AF_INET6 sockets.
type SockaddrL2TPIP6 struct {
Addr [16]byte
ZoneId uint32
ConnId uint32
raw RawSockaddrL2TPIP6
}
func (sa *SockaddrL2TPIP6) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_INET6
sa.raw.Conn_id = sa.ConnId
sa.raw.Scope_id = sa.ZoneId
for i := 0; i < len(sa.Addr); i++ {
sa.raw.Addr[i] = sa.Addr[i]
}
return unsafe.Pointer(&sa.raw), SizeofSockaddrL2TPIP6, nil
}
// SockaddrIUCV implements the Sockaddr interface for AF_IUCV sockets.
type SockaddrIUCV struct {
UserID string
Name string
raw RawSockaddrIUCV
}
func (sa *SockaddrIUCV) sockaddr() (unsafe.Pointer, _Socklen, error) {
sa.raw.Family = AF_IUCV
// These are EBCDIC encoded by the kernel, but we still need to pad them
// with blanks. Initializing with blanks allows the caller to feed in either
// a padded or an unpadded string.
for i := 0; i < 8; i++ {
sa.raw.Nodeid[i] = ' '
sa.raw.User_id[i] = ' '
sa.raw.Name[i] = ' '
}
if len(sa.UserID) > 8 || len(sa.Name) > 8 {
return nil, 0, EINVAL
}
for i, b := range []byte(sa.UserID[:]) {
sa.raw.User_id[i] = int8(b)
}
for i, b := range []byte(sa.Name[:]) {
sa.raw.Name[i] = int8(b)
}
return unsafe.Pointer(&sa.raw), SizeofSockaddrIUCV, nil
}
func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
switch rsa.Addr.Family {
case AF_NETLINK:
pp := (*RawSockaddrNetlink)(unsafe.Pointer(rsa))
sa := new(SockaddrNetlink)
sa.Family = pp.Family
sa.Pad = pp.Pad
sa.Pid = pp.Pid
sa.Groups = pp.Groups
return sa, nil
case AF_PACKET:
pp := (*RawSockaddrLinklayer)(unsafe.Pointer(rsa))
sa := new(SockaddrLinklayer)
sa.Protocol = pp.Protocol
sa.Ifindex = int(pp.Ifindex)
sa.Hatype = pp.Hatype
sa.Pkttype = pp.Pkttype
sa.Halen = pp.Halen
for i := 0; i < len(sa.Addr); i++ {
sa.Addr[i] = pp.Addr[i]
}
return sa, nil
case AF_UNIX:
pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa))
sa := new(SockaddrUnix)
if pp.Path[0] == 0 {
// "Abstract" Unix domain socket.
// Rewrite leading NUL as @ for textual display.
// (This is the standard convention.)
// Not friendly to overwrite in place,
// but the callers below don't care.
pp.Path[0] = '@'
}
// Assume path ends at NUL.
// This is not technically the Linux semantics for
// abstract Unix domain sockets--they are supposed
// to be uninterpreted fixed-size binary blobs--but
// everyone uses this convention.
n := 0
for n < len(pp.Path) && pp.Path[n] != 0 {
n++
}
bytes := (*[len(pp.Path)]byte)(unsafe.Pointer(&pp.Path[0]))[0:n]
sa.Name = string(bytes)
return sa, nil
case AF_INET:
proto, err := GetsockoptInt(fd, SOL_SOCKET, SO_PROTOCOL)
if err != nil {
return nil, err
}
switch proto {
case IPPROTO_L2TP:
pp := (*RawSockaddrL2TPIP)(unsafe.Pointer(rsa))
sa := new(SockaddrL2TPIP)
sa.ConnId = pp.Conn_id
for i := 0; i < len(sa.Addr); i++ {
sa.Addr[i] = pp.Addr[i]
}
return sa, nil
default:
pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
sa := new(SockaddrInet4)
p := (*[2]byte)(unsafe.Pointer(&pp.Port))
sa.Port = int(p[0])<<8 + int(p[1])
for i := 0; i < len(sa.Addr); i++ {
sa.Addr[i] = pp.Addr[i]
}
return sa, nil
}
case AF_INET6:
proto, err := GetsockoptInt(fd, SOL_SOCKET, SO_PROTOCOL)
if err != nil {
return nil, err
}
switch proto {
case IPPROTO_L2TP:
pp := (*RawSockaddrL2TPIP6)(unsafe.Pointer(rsa))
sa := new(SockaddrL2TPIP6)
sa.ConnId = pp.Conn_id
sa.ZoneId = pp.Scope_id
for i := 0; i < len(sa.Addr); i++ {
sa.Addr[i] = pp.Addr[i]
}
return sa, nil
default:
pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
sa := new(SockaddrInet6)
p := (*[2]byte)(unsafe.Pointer(&pp.Port))
sa.Port = int(p[0])<<8 + int(p[1])
sa.ZoneId = pp.Scope_id
for i := 0; i < len(sa.Addr); i++ {
sa.Addr[i] = pp.Addr[i]
}
return sa, nil
}
case AF_VSOCK:
pp := (*RawSockaddrVM)(unsafe.Pointer(rsa))
sa := &SockaddrVM{
CID: pp.Cid,
Port: pp.Port,
}
return sa, nil
case AF_BLUETOOTH:
proto, err := GetsockoptInt(fd, SOL_SOCKET, SO_PROTOCOL)
if err != nil {
return nil, err
}
// only BTPROTO_L2CAP and BTPROTO_RFCOMM can accept connections
switch proto {
case BTPROTO_L2CAP:
pp := (*RawSockaddrL2)(unsafe.Pointer(rsa))
sa := &SockaddrL2{
PSM: pp.Psm,
CID: pp.Cid,
Addr: pp.Bdaddr,
AddrType: pp.Bdaddr_type,
}
return sa, nil
case BTPROTO_RFCOMM:
pp := (*RawSockaddrRFCOMM)(unsafe.Pointer(rsa))
sa := &SockaddrRFCOMM{
Channel: pp.Channel,
Addr: pp.Bdaddr,
}
return sa, nil
}
case AF_XDP:
pp := (*RawSockaddrXDP)(unsafe.Pointer(rsa))
sa := &SockaddrXDP{
Flags: pp.Flags,
Ifindex: pp.Ifindex,
QueueID: pp.Queue_id,
SharedUmemFD: pp.Shared_umem_fd,
}
return sa, nil
case AF_PPPOX:
pp := (*RawSockaddrPPPoX)(unsafe.Pointer(rsa))
if binary.BigEndian.Uint32(pp[2:6]) != px_proto_oe {
return nil, EINVAL
}
sa := &SockaddrPPPoE{
SID: binary.BigEndian.Uint16(pp[6:8]),
Remote: pp[8:14],
}
for i := 14; i < 14+IFNAMSIZ; i++ {
if pp[i] == 0 {
sa.Dev = string(pp[14:i])
break
}
}
return sa, nil
case AF_TIPC:
pp := (*RawSockaddrTIPC)(unsafe.Pointer(rsa))
sa := &SockaddrTIPC{
Scope: int(pp.Scope),
}
// Determine which union variant is present in pp.Addr by checking
// pp.Addrtype.
switch pp.Addrtype {
case TIPC_SERVICE_RANGE:
sa.Addr = (*TIPCServiceRange)(unsafe.Pointer(&pp.Addr))
case TIPC_SERVICE_ADDR:
sa.Addr = (*TIPCServiceName)(unsafe.Pointer(&pp.Addr))
case TIPC_SOCKET_ADDR:
sa.Addr = (*TIPCSocketAddr)(unsafe.Pointer(&pp.Addr))
default:
return nil, EINVAL
}
return sa, nil
case AF_IUCV:
pp := (*RawSockaddrIUCV)(unsafe.Pointer(rsa))
var user [8]byte
var name [8]byte
for i := 0; i < 8; i++ {
user[i] = byte(pp.User_id[i])
name[i] = byte(pp.Name[i])
}
sa := &SockaddrIUCV{
UserID: string(user[:]),
Name: string(name[:]),
}
return sa, nil
case AF_CAN:
pp := (*RawSockaddrCAN)(unsafe.Pointer(rsa))
sa := &SockaddrCAN{
Ifindex: int(pp.Ifindex),
}
rx := (*[4]byte)(unsafe.Pointer(&sa.RxID))
for i := 0; i < 4; i++ {
rx[i] = pp.Addr[i]
}
tx := (*[4]byte)(unsafe.Pointer(&sa.TxID))
for i := 0; i < 4; i++ {
tx[i] = pp.Addr[i+4]
}
return sa, nil
}
return nil, EAFNOSUPPORT
}
func Accept(fd int) (nfd int, sa Sockaddr, err error) {
var rsa RawSockaddrAny
var len _Socklen = SizeofSockaddrAny
nfd, err = accept(fd, &rsa, &len)
if err != nil {
return
}
sa, err = anyToSockaddr(fd, &rsa)
if err != nil {
Close(nfd)
nfd = 0
}
return
}
func Accept4(fd int, flags int) (nfd int, sa Sockaddr, err error) {
var rsa RawSockaddrAny
var len _Socklen = SizeofSockaddrAny
nfd, err = accept4(fd, &rsa, &len, flags)
if err != nil {
return
}
if len > SizeofSockaddrAny {
panic("RawSockaddrAny too small")
}
sa, err = anyToSockaddr(fd, &rsa)
if err != nil {
Close(nfd)
nfd = 0
}
return
}
func Getsockname(fd int) (sa Sockaddr, err error) {
var rsa RawSockaddrAny
var len _Socklen = SizeofSockaddrAny
if err = getsockname(fd, &rsa, &len); err != nil {
return
}
return anyToSockaddr(fd, &rsa)
}
func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) {
var value IPMreqn
vallen := _Socklen(SizeofIPMreqn)
err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
return &value, err
}
func GetsockoptUcred(fd, level, opt int) (*Ucred, error) {
var value Ucred
vallen := _Socklen(SizeofUcred)
err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
return &value, err
}
func GetsockoptTCPInfo(fd, level, opt int) (*TCPInfo, error) {
var value TCPInfo
vallen := _Socklen(SizeofTCPInfo)
err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
return &value, err
}
// GetsockoptString returns the string value of the socket option opt for the
// socket associated with fd at the given socket level.
func GetsockoptString(fd, level, opt int) (string, error) {
buf := make([]byte, 256)
vallen := _Socklen(len(buf))
err := getsockopt(fd, level, opt, unsafe.Pointer(&buf[0]), &vallen)
if err != nil {
if err == ERANGE {
buf = make([]byte, vallen)
err = getsockopt(fd, level, opt, unsafe.Pointer(&buf[0]), &vallen)
}
if err != nil {
return "", err
}
}
return string(buf[:vallen-1]), nil
}
func GetsockoptTpacketStats(fd, level, opt int) (*TpacketStats, error) {
var value TpacketStats
vallen := _Socklen(SizeofTpacketStats)
err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
return &value, err
}
func GetsockoptTpacketStatsV3(fd, level, opt int) (*TpacketStatsV3, error) {
var value TpacketStatsV3
vallen := _Socklen(SizeofTpacketStatsV3)
err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
return &value, err
}
func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) {
return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq))
}
func SetsockoptPacketMreq(fd, level, opt int, mreq *PacketMreq) error {
return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq))
}
// SetsockoptSockFprog attaches a classic BPF or an extended BPF program to a
// socket to filter incoming packets. See 'man 7 socket' for usage information.
func SetsockoptSockFprog(fd, level, opt int, fprog *SockFprog) error {
return setsockopt(fd, level, opt, unsafe.Pointer(fprog), unsafe.Sizeof(*fprog))
}
func SetsockoptCanRawFilter(fd, level, opt int, filter []CanFilter) error {
var p unsafe.Pointer
if len(filter) > 0 {
p = unsafe.Pointer(&filter[0])
}
return setsockopt(fd, level, opt, p, uintptr(len(filter)*SizeofCanFilter))
}
func SetsockoptTpacketReq(fd, level, opt int, tp *TpacketReq) error {
return setsockopt(fd, level, opt, unsafe.Pointer(tp), unsafe.Sizeof(*tp))
}
func SetsockoptTpacketReq3(fd, level, opt int, tp *TpacketReq3) error {
return setsockopt(fd, level, opt, unsafe.Pointer(tp), unsafe.Sizeof(*tp))
}
// Keyctl Commands (http://man7.org/linux/man-pages/man2/keyctl.2.html)
// KeyctlInt calls keyctl commands in which each argument is an int.
// These commands are KEYCTL_REVOKE, KEYCTL_CHOWN, KEYCTL_CLEAR, KEYCTL_LINK,
// KEYCTL_UNLINK, KEYCTL_NEGATE, KEYCTL_SET_REQKEY_KEYRING, KEYCTL_SET_TIMEOUT,
// KEYCTL_ASSUME_AUTHORITY, KEYCTL_SESSION_TO_PARENT, KEYCTL_REJECT,
// KEYCTL_INVALIDATE, and KEYCTL_GET_PERSISTENT.
//sys KeyctlInt(cmd int, arg2 int, arg3 int, arg4 int, arg5 int) (ret int, err error) = SYS_KEYCTL
// KeyctlBuffer calls keyctl commands in which the third and fourth
// arguments are a buffer and its length, respectively.
// These commands are KEYCTL_UPDATE, KEYCTL_READ, and KEYCTL_INSTANTIATE.
//sys KeyctlBuffer(cmd int, arg2 int, buf []byte, arg5 int) (ret int, err error) = SYS_KEYCTL
// KeyctlString calls keyctl commands which return a string.
// These commands are KEYCTL_DESCRIBE and KEYCTL_GET_SECURITY.
func KeyctlString(cmd int, id int) (string, error) {
// We must loop as the string data may change in between the syscalls.
// We could allocate a large buffer here to reduce the chance that the
// syscall needs to be called twice; however, this is unnecessary as
// the performance loss is negligible.
var buffer []byte
for {
// Try to fill the buffer with data
length, err := KeyctlBuffer(cmd, id, buffer, 0)
if err != nil {
return "", err
}
// Check if the data was written
if length <= len(buffer) {
// Exclude the null terminator
return string(buffer[:length-1]), nil
}
// Make a bigger buffer if needed
buffer = make([]byte, length)
}
}
// Keyctl commands with special signatures.
// KeyctlGetKeyringID implements the KEYCTL_GET_KEYRING_ID command.
// See the full documentation at:
// http://man7.org/linux/man-pages/man3/keyctl_get_keyring_ID.3.html
func KeyctlGetKeyringID(id int, create bool) (ringid int, err error) {
createInt := 0
if create {
createInt = 1
}
return KeyctlInt(KEYCTL_GET_KEYRING_ID, id, createInt, 0, 0)
}
// KeyctlSetperm implements the KEYCTL_SETPERM command. The perm value is the
// key handle permission mask as described in the "keyctl setperm" section of
// http://man7.org/linux/man-pages/man1/keyctl.1.html.
// See the full documentation at:
// http://man7.org/linux/man-pages/man3/keyctl_setperm.3.html
func KeyctlSetperm(id int, perm uint32) error {
_, err := KeyctlInt(KEYCTL_SETPERM, id, int(perm), 0, 0)
return err
}
//sys keyctlJoin(cmd int, arg2 string) (ret int, err error) = SYS_KEYCTL
// KeyctlJoinSessionKeyring implements the KEYCTL_JOIN_SESSION_KEYRING command.
// See the full documentation at:
// http://man7.org/linux/man-pages/man3/keyctl_join_session_keyring.3.html
func KeyctlJoinSessionKeyring(name string) (ringid int, err error) {
return keyctlJoin(KEYCTL_JOIN_SESSION_KEYRING, name)
}
//sys keyctlSearch(cmd int, arg2 int, arg3 string, arg4 string, arg5 int) (ret int, err error) = SYS_KEYCTL
// KeyctlSearch implements the KEYCTL_SEARCH command.
// See the full documentation at:
// http://man7.org/linux/man-pages/man3/keyctl_search.3.html
func KeyctlSearch(ringid int, keyType, description string, destRingid int) (id int, err error) {
return keyctlSearch(KEYCTL_SEARCH, ringid, keyType, description, destRingid)
}
//sys keyctlIOV(cmd int, arg2 int, payload []Iovec, arg5 int) (err error) = SYS_KEYCTL
// KeyctlInstantiateIOV implements the KEYCTL_INSTANTIATE_IOV command. This
// command is similar to KEYCTL_INSTANTIATE, except that the payload is a slice
// of Iovec (each of which represents a buffer) instead of a single buffer.
// See the full documentation at:
// http://man7.org/linux/man-pages/man3/keyctl_instantiate_iov.3.html
func KeyctlInstantiateIOV(id int, payload []Iovec, ringid int) error {
return keyctlIOV(KEYCTL_INSTANTIATE_IOV, id, payload, ringid)
}
//sys keyctlDH(cmd int, arg2 *KeyctlDHParams, buf []byte) (ret int, err error) = SYS_KEYCTL
// KeyctlDHCompute implements the KEYCTL_DH_COMPUTE command. This command
// computes a Diffie-Hellman shared secret based on the provide params. The
// secret is written to the provided buffer and the returned size is the number
// of bytes written (returning an error if there is insufficient space in the
// buffer). If a nil buffer is passed in, this function returns the minimum
// buffer length needed to store the appropriate data. Note that this differs
// from KEYCTL_READ's behavior which always returns the requested payload size.
// See the full documentation at:
// http://man7.org/linux/man-pages/man3/keyctl_dh_compute.3.html
func KeyctlDHCompute(params *KeyctlDHParams, buffer []byte) (size int, err error) {
return keyctlDH(KEYCTL_DH_COMPUTE, params, buffer)
}
// KeyctlRestrictKeyring implements the KEYCTL_RESTRICT_KEYRING command. This
// command limits the set of keys that can be linked to the keyring, regardless
// of keyring permissions. The command requires the "setattr" permission.
//
// When called with an empty keyType the command locks the keyring, preventing
// any further keys from being linked to the keyring.
//
// The "asymmetric" keyType defines restrictions requiring key payloads to be
// DER encoded X.509 certificates signed by keys in another keyring. Restrictions
// for "asymmetric" include "builtin_trusted", "builtin_and_secondary_trusted",
// "key_or_keyring:<key>", and "key_or_keyring:<key>:chain".
//
// As of Linux 4.12, only the "asymmetric" keyType defines type-specific
// restrictions.
//
// See the full documentation at:
// http://man7.org/linux/man-pages/man3/keyctl_restrict_keyring.3.html
// http://man7.org/linux/man-pages/man2/keyctl.2.html
func KeyctlRestrictKeyring(ringid int, keyType string, restriction string) error {
if keyType == "" {
return keyctlRestrictKeyring(KEYCTL_RESTRICT_KEYRING, ringid)
}
return keyctlRestrictKeyringByType(KEYCTL_RESTRICT_KEYRING, ringid, keyType, restriction)
}
//sys keyctlRestrictKeyringByType(cmd int, arg2 int, keyType string, restriction string) (err error) = SYS_KEYCTL
//sys keyctlRestrictKeyring(cmd int, arg2 int) (err error) = SYS_KEYCTL
func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
var msg Msghdr
var rsa RawSockaddrAny
msg.Name = (*byte)(unsafe.Pointer(&rsa))
msg.Namelen = uint32(SizeofSockaddrAny)
var iov Iovec
if len(p) > 0 {
iov.Base = &p[0]
iov.SetLen(len(p))
}
var dummy byte
if len(oob) > 0 {
if len(p) == 0 {
var sockType int
sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
if err != nil {
return
}
// receive at least one normal byte
if sockType != SOCK_DGRAM {
iov.Base = &dummy
iov.SetLen(1)
}
}
msg.Control = &oob[0]
msg.SetControllen(len(oob))
}
msg.Iov = &iov
msg.Iovlen = 1
if n, err = recvmsg(fd, &msg, flags); err != nil {
return
}
oobn = int(msg.Controllen)
recvflags = int(msg.Flags)
// source address is only specified if the socket is unconnected
if rsa.Addr.Family != AF_UNSPEC {
from, err = anyToSockaddr(fd, &rsa)
}
return
}
func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
_, err = SendmsgN(fd, p, oob, to, flags)
return
}
func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
var ptr unsafe.Pointer
var salen _Socklen
if to != nil {
var err error
ptr, salen, err = to.sockaddr()
if err != nil {
return 0, err
}
}
var msg Msghdr
msg.Name = (*byte)(ptr)
msg.Namelen = uint32(salen)
var iov Iovec
if len(p) > 0 {
iov.Base = &p[0]
iov.SetLen(len(p))
}
var dummy byte
if len(oob) > 0 {
if len(p) == 0 {
var sockType int
sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE)
if err != nil {
return 0, err
}
// send at least one normal byte
if sockType != SOCK_DGRAM {
iov.Base = &dummy
iov.SetLen(1)
}
}
msg.Control = &oob[0]
msg.SetControllen(len(oob))
}
msg.Iov = &iov
msg.Iovlen = 1
if n, err = sendmsg(fd, &msg, flags); err != nil {
return 0, err
}
if len(oob) > 0 && len(p) == 0 {
n = 0
}
return n, nil
}
// BindToDevice binds the socket associated with fd to device.
func BindToDevice(fd int, device string) (err error) {
return SetsockoptString(fd, SOL_SOCKET, SO_BINDTODEVICE, device)
}
//sys ptrace(request int, pid int, addr uintptr, data uintptr) (err error)
func ptracePeek(req int, pid int, addr uintptr, out []byte) (count int, err error) {
// The peek requests are machine-size oriented, so we wrap it
// to retrieve arbitrary-length data.
// The ptrace syscall differs from glibc's ptrace.
// Peeks returns the word in *data, not as the return value.
var buf [SizeofPtr]byte
// Leading edge. PEEKTEXT/PEEKDATA don't require aligned
// access (PEEKUSER warns that it might), but if we don't
// align our reads, we might straddle an unmapped page
// boundary and not get the bytes leading up to the page
// boundary.
n := 0
if addr%SizeofPtr != 0 {
err = ptrace(req, pid, addr-addr%SizeofPtr, uintptr(unsafe.Pointer(&buf[0])))
if err != nil {
return 0, err
}
n += copy(out, buf[addr%SizeofPtr:])
out = out[n:]
}
// Remainder.
for len(out) > 0 {
// We use an internal buffer to guarantee alignment.
// It's not documented if this is necessary, but we're paranoid.
err = ptrace(req, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0])))
if err != nil {
return n, err
}
copied := copy(out, buf[0:])
n += copied
out = out[copied:]
}
return n, nil
}
func PtracePeekText(pid int, addr uintptr, out []byte) (count int, err error) {
return ptracePeek(PTRACE_PEEKTEXT, pid, addr, out)
}
func PtracePeekData(pid int, addr uintptr, out []byte) (count int, err error) {
return ptracePeek(PTRACE_PEEKDATA, pid, addr, out)
}
func PtracePeekUser(pid int, addr uintptr, out []byte) (count int, err error) {
return ptracePeek(PTRACE_PEEKUSR, pid, addr, out)
}
func ptracePoke(pokeReq int, peekReq int, pid int, addr uintptr, data []byte) (count int, err error) {
// As for ptracePeek, we need to align our accesses to deal
// with the possibility of straddling an invalid page.
// Leading edge.
n := 0
if addr%SizeofPtr != 0 {
var buf [SizeofPtr]byte
err = ptrace(peekReq, pid, addr-addr%SizeofPtr, uintptr(unsafe.Pointer(&buf[0])))
if err != nil {
return 0, err
}
n += copy(buf[addr%SizeofPtr:], data)
word := *((*uintptr)(unsafe.Pointer(&buf[0])))
err = ptrace(pokeReq, pid, addr-addr%SizeofPtr, word)
if err != nil {
return 0, err
}
data = data[n:]
}
// Interior.
for len(data) > SizeofPtr {
word := *((*uintptr)(unsafe.Pointer(&data[0])))
err = ptrace(pokeReq, pid, addr+uintptr(n), word)
if err != nil {
return n, err
}
n += SizeofPtr
data = data[SizeofPtr:]
}
// Trailing edge.
if len(data) > 0 {
var buf [SizeofPtr]byte
err = ptrace(peekReq, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0])))
if err != nil {
return n, err
}
copy(buf[0:], data)
word := *((*uintptr)(unsafe.Pointer(&buf[0])))
err = ptrace(pokeReq, pid, addr+uintptr(n), word)
if err != nil {
return n, err
}
n += len(data)
}
return n, nil
}
func PtracePokeText(pid int, addr uintptr, data []byte) (count int, err error) {
return ptracePoke(PTRACE_POKETEXT, PTRACE_PEEKTEXT, pid, addr, data)
}
func PtracePokeData(pid int, addr uintptr, data []byte) (count int, err error) {
return ptracePoke(PTRACE_POKEDATA, PTRACE_PEEKDATA, pid, addr, data)
}
func PtracePokeUser(pid int, addr uintptr, data []byte) (count int, err error) {
return ptracePoke(PTRACE_POKEUSR, PTRACE_PEEKUSR, pid, addr, data)
}
func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout)))
}
func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
}
func PtraceSetOptions(pid int, options int) (err error) {
return ptrace(PTRACE_SETOPTIONS, pid, 0, uintptr(options))
}
func PtraceGetEventMsg(pid int) (msg uint, err error) {
var data _C_long
err = ptrace(PTRACE_GETEVENTMSG, pid, 0, uintptr(unsafe.Pointer(&data)))
msg = uint(data)
return
}
func PtraceCont(pid int, signal int) (err error) {
return ptrace(PTRACE_CONT, pid, 0, uintptr(signal))
}
func PtraceSyscall(pid int, signal int) (err error) {
return ptrace(PTRACE_SYSCALL, pid, 0, uintptr(signal))
}
func PtraceSingleStep(pid int) (err error) { return ptrace(PTRACE_SINGLESTEP, pid, 0, 0) }
func PtraceInterrupt(pid int) (err error) { return ptrace(PTRACE_INTERRUPT, pid, 0, 0) }
func PtraceAttach(pid int) (err error) { return ptrace(PTRACE_ATTACH, pid, 0, 0) }
func PtraceSeize(pid int) (err error) { return ptrace(PTRACE_SEIZE, pid, 0, 0) }
func PtraceDetach(pid int) (err error) { return ptrace(PTRACE_DETACH, pid, 0, 0) }
//sys reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error)
func Reboot(cmd int) (err error) {
return reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, "")
}
func direntIno(buf []byte) (uint64, bool) {
return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
}
func direntReclen(buf []byte) (uint64, bool) {
return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
}
func direntNamlen(buf []byte) (uint64, bool) {
reclen, ok := direntReclen(buf)
if !ok {
return 0, false
}
return reclen - uint64(unsafe.Offsetof(Dirent{}.Name)), true
}
//sys mount(source string, target string, fstype string, flags uintptr, data *byte) (err error)
func Mount(source string, target string, fstype string, flags uintptr, data string) (err error) {
// Certain file systems get rather angry and EINVAL if you give
// them an empty string of data, rather than NULL.
if data == "" {
return mount(source, target, fstype, flags, nil)
}
datap, err := BytePtrFromString(data)
if err != nil {
return err
}
return mount(source, target, fstype, flags, datap)
}
func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
if raceenabled {
raceReleaseMerge(unsafe.Pointer(&ioSync))
}
return sendfile(outfd, infd, offset, count)
}
// Sendto
// Recvfrom
// Socketpair
/*
* Direct access
*/
//sys Acct(path string) (err error)
//sys AddKey(keyType string, description string, payload []byte, ringid int) (id int, err error)
//sys Adjtimex(buf *Timex) (state int, err error)
//sysnb Capget(hdr *CapUserHeader, data *CapUserData) (err error)
//sysnb Capset(hdr *CapUserHeader, data *CapUserData) (err error)
//sys Chdir(path string) (err error)
//sys Chroot(path string) (err error)
//sys ClockGetres(clockid int32, res *Timespec) (err error)
//sys ClockGettime(clockid int32, time *Timespec) (err error)
//sys ClockNanosleep(clockid int32, flags int, request *Timespec, remain *Timespec) (err error)
//sys Close(fd int) (err error)
//sys CopyFileRange(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int, err error)
//sys DeleteModule(name string, flags int) (err error)
//sys Dup(oldfd int) (fd int, err error)
func Dup2(oldfd, newfd int) error {
// Android O and newer blocks dup2; riscv and arm64 don't implement dup2.
if runtime.GOOS == "android" || runtime.GOARCH == "riscv64" || runtime.GOARCH == "arm64" {
return Dup3(oldfd, newfd, 0)
}
return dup2(oldfd, newfd)
}
//sys Dup3(oldfd int, newfd int, flags int) (err error)
//sysnb EpollCreate1(flag int) (fd int, err error)
//sysnb EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error)
//sys Eventfd(initval uint, flags int) (fd int, err error) = SYS_EVENTFD2
//sys Exit(code int) = SYS_EXIT_GROUP
//sys Fallocate(fd int, mode uint32, off int64, len int64) (err error)
//sys Fchdir(fd int) (err error)
//sys Fchmod(fd int, mode uint32) (err error)
//sys Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error)
//sys Fdatasync(fd int) (err error)
//sys Fgetxattr(fd int, attr string, dest []byte) (sz int, err error)
//sys FinitModule(fd int, params string, flags int) (err error)
//sys Flistxattr(fd int, dest []byte) (sz int, err error)
//sys Flock(fd int, how int) (err error)
//sys Fremovexattr(fd int, attr string) (err error)
//sys Fsetxattr(fd int, attr string, dest []byte, flags int) (err error)
//sys Fsync(fd int) (err error)
//sys Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64
//sysnb Getpgid(pid int) (pgid int, err error)
func Getpgrp() (pid int) {
pid, _ = Getpgid(0)
return
}
//sysnb Getpid() (pid int)
//sysnb Getppid() (ppid int)
//sys Getpriority(which int, who int) (prio int, err error)
//sys Getrandom(buf []byte, flags int) (n int, err error)
//sysnb Getrusage(who int, rusage *Rusage) (err error)
//sysnb Getsid(pid int) (sid int, err error)
//sysnb Gettid() (tid int)
//sys Getxattr(path string, attr string, dest []byte) (sz int, err error)
//sys InitModule(moduleImage []byte, params string) (err error)
//sys InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error)
//sysnb InotifyInit1(flags int) (fd int, err error)
//sysnb InotifyRmWatch(fd int, watchdesc uint32) (success int, err error)
//sysnb Kill(pid int, sig syscall.Signal) (err error)
//sys Klogctl(typ int, buf []byte) (n int, err error) = SYS_SYSLOG
//sys Lgetxattr(path string, attr string, dest []byte) (sz int, err error)
//sys Listxattr(path string, dest []byte) (sz int, err error)
//sys Llistxattr(path string, dest []byte) (sz int, err error)
//sys Lremovexattr(path string, attr string) (err error)
//sys Lsetxattr(path string, attr string, data []byte, flags int) (err error)
//sys MemfdCreate(name string, flags int) (fd int, err error)
//sys Mkdirat(dirfd int, path string, mode uint32) (err error)
//sys Mknodat(dirfd int, path string, mode uint32, dev int) (err error)
//sys Nanosleep(time *Timespec, leftover *Timespec) (err error)
//sys PerfEventOpen(attr *PerfEventAttr, pid int, cpu int, groupFd int, flags int) (fd int, err error)
//sys PivotRoot(newroot string, putold string) (err error) = SYS_PIVOT_ROOT
//sysnb prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT64
//sys Prctl(option int, arg2 uintptr, arg3 uintptr, arg4 uintptr, arg5 uintptr) (err error)
//sys Pselect(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timespec, sigmask *Sigset_t) (n int, err error) = SYS_PSELECT6
//sys read(fd int, p []byte) (n int, err error)
//sys Removexattr(path string, attr string) (err error)
//sys Renameat2(olddirfd int, oldpath string, newdirfd int, newpath string, flags uint) (err error)
//sys RequestKey(keyType string, description string, callback string, destRingid int) (id int, err error)
//sys Setdomainname(p []byte) (err error)
//sys Sethostname(p []byte) (err error)
//sysnb Setpgid(pid int, pgid int) (err error)
//sysnb Setsid() (pid int, err error)
//sysnb Settimeofday(tv *Timeval) (err error)
//sys Setns(fd int, nstype int) (err error)
// PrctlRetInt performs a prctl operation specified by option and further
// optional arguments arg2 through arg5 depending on option. It returns a
// non-negative integer that is returned by the prctl syscall.
func PrctlRetInt(option int, arg2 uintptr, arg3 uintptr, arg4 uintptr, arg5 uintptr) (int, error) {
ret, _, err := Syscall6(SYS_PRCTL, uintptr(option), uintptr(arg2), uintptr(arg3), uintptr(arg4), uintptr(arg5), 0)
if err != 0 {
return 0, err
}
return int(ret), nil
}
// issue 1435.
// On linux Setuid and Setgid only affects the current thread, not the process.
// This does not match what most callers expect so we must return an error
// here rather than letting the caller think that the call succeeded.
func Setuid(uid int) (err error) {
return EOPNOTSUPP
}
func Setgid(uid int) (err error) {
return EOPNOTSUPP
}
// SetfsgidRetGid sets fsgid for current thread and returns previous fsgid set.
// setfsgid(2) will return a non-nil error only if its caller lacks CAP_SETUID capability.
// If the call fails due to other reasons, current fsgid will be returned.
func SetfsgidRetGid(gid int) (int, error) {
return setfsgid(gid)
}
// SetfsuidRetUid sets fsuid for current thread and returns previous fsuid set.
// setfsgid(2) will return a non-nil error only if its caller lacks CAP_SETUID capability
// If the call fails due to other reasons, current fsuid will be returned.
func SetfsuidRetUid(uid int) (int, error) {
return setfsuid(uid)
}
func Setfsgid(gid int) error {
_, err := setfsgid(gid)
return err
}
func Setfsuid(uid int) error {
_, err := setfsuid(uid)
return err
}
func Signalfd(fd int, sigmask *Sigset_t, flags int) (newfd int, err error) {
return signalfd(fd, sigmask, _C__NSIG/8, flags)
}
//sys Setpriority(which int, who int, prio int) (err error)
//sys Setxattr(path string, attr string, data []byte, flags int) (err error)
//sys signalfd(fd int, sigmask *Sigset_t, maskSize uintptr, flags int) (newfd int, err error) = SYS_SIGNALFD4
//sys Statx(dirfd int, path string, flags int, mask int, stat *Statx_t) (err error)
//sys Sync()
//sys Syncfs(fd int) (err error)
//sysnb Sysinfo(info *Sysinfo_t) (err error)
//sys Tee(rfd int, wfd int, len int, flags int) (n int64, err error)
//sysnb TimerfdCreate(clockid int, flags int) (fd int, err error)
//sysnb TimerfdGettime(fd int, currValue *ItimerSpec) (err error)
//sysnb TimerfdSettime(fd int, flags int, newValue *ItimerSpec, oldValue *ItimerSpec) (err error)
//sysnb Tgkill(tgid int, tid int, sig syscall.Signal) (err error)
//sysnb Times(tms *Tms) (ticks uintptr, err error)
//sysnb Umask(mask int) (oldmask int)
//sysnb Uname(buf *Utsname) (err error)
//sys Unmount(target string, flags int) (err error) = SYS_UMOUNT2
//sys Unshare(flags int) (err error)
//sys write(fd int, p []byte) (n int, err error)
//sys exitThread(code int) (err error) = SYS_EXIT
//sys readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ
//sys writelen(fd int, p *byte, np int) (n int, err error) = SYS_WRITE
//sys readv(fd int, iovs []Iovec) (n int, err error) = SYS_READV
//sys writev(fd int, iovs []Iovec) (n int, err error) = SYS_WRITEV
//sys preadv(fd int, iovs []Iovec, offs_l uintptr, offs_h uintptr) (n int, err error) = SYS_PREADV
//sys pwritev(fd int, iovs []Iovec, offs_l uintptr, offs_h uintptr) (n int, err error) = SYS_PWRITEV
//sys preadv2(fd int, iovs []Iovec, offs_l uintptr, offs_h uintptr, flags int) (n int, err error) = SYS_PREADV2
//sys pwritev2(fd int, iovs []Iovec, offs_l uintptr, offs_h uintptr, flags int) (n int, err error) = SYS_PWRITEV2
func bytes2iovec(bs [][]byte) []Iovec {
iovecs := make([]Iovec, len(bs))
for i, b := range bs {
iovecs[i].SetLen(len(b))
if len(b) > 0 {
iovecs[i].Base = &b[0]
} else {
iovecs[i].Base = (*byte)(unsafe.Pointer(&_zero))
}
}
return iovecs
}
// offs2lohi splits offs into its lower and upper unsigned long. On 64-bit
// systems, hi will always be 0. On 32-bit systems, offs will be split in half.
// preadv/pwritev chose this calling convention so they don't need to add a
// padding-register for alignment on ARM.
func offs2lohi(offs int64) (lo, hi uintptr) {
return uintptr(offs), uintptr(uint64(offs) >> SizeofLong)
}
func Readv(fd int, iovs [][]byte) (n int, err error) {
iovecs := bytes2iovec(iovs)
n, err = readv(fd, iovecs)
readvRacedetect(iovecs, n, err)
return n, err
}
func Preadv(fd int, iovs [][]byte, offset int64) (n int, err error) {
iovecs := bytes2iovec(iovs)
lo, hi := offs2lohi(offset)
n, err = preadv(fd, iovecs, lo, hi)
readvRacedetect(iovecs, n, err)
return n, err
}
func Preadv2(fd int, iovs [][]byte, offset int64, flags int) (n int, err error) {
iovecs := bytes2iovec(iovs)
lo, hi := offs2lohi(offset)
n, err = preadv2(fd, iovecs, lo, hi, flags)
readvRacedetect(iovecs, n, err)
return n, err
}
func readvRacedetect(iovecs []Iovec, n int, err error) {
if !raceenabled {
return
}
for i := 0; n > 0 && i < len(iovecs); i++ {
m := int(iovecs[i].Len)
if m > n {
m = n
}
n -= m
if m > 0 {
raceWriteRange(unsafe.Pointer(iovecs[i].Base), m)
}
}
if err == nil {
raceAcquire(unsafe.Pointer(&ioSync))
}
}
func Writev(fd int, iovs [][]byte) (n int, err error) {
iovecs := bytes2iovec(iovs)
if raceenabled {
raceReleaseMerge(unsafe.Pointer(&ioSync))
}
n, err = writev(fd, iovecs)
writevRacedetect(iovecs, n)
return n, err
}
func Pwritev(fd int, iovs [][]byte, offset int64) (n int, err error) {
iovecs := bytes2iovec(iovs)
if raceenabled {
raceReleaseMerge(unsafe.Pointer(&ioSync))
}
lo, hi := offs2lohi(offset)
n, err = pwritev(fd, iovecs, lo, hi)
writevRacedetect(iovecs, n)
return n, err
}
func Pwritev2(fd int, iovs [][]byte, offset int64, flags int) (n int, err error) {
iovecs := bytes2iovec(iovs)
if raceenabled {
raceReleaseMerge(unsafe.Pointer(&ioSync))
}
lo, hi := offs2lohi(offset)
n, err = pwritev2(fd, iovecs, lo, hi, flags)
writevRacedetect(iovecs, n)
return n, err
}
func writevRacedetect(iovecs []Iovec, n int) {
if !raceenabled {
return
}
for i := 0; n > 0 && i < len(iovecs); i++ {
m := int(iovecs[i].Len)
if m > n {
m = n
}
n -= m
if m > 0 {
raceReadRange(unsafe.Pointer(iovecs[i].Base), m)
}
}
}
// mmap varies by architecture; see syscall_linux_*.go.
//sys munmap(addr uintptr, length uintptr) (err error)
var mapper = &mmapper{
active: make(map[*byte][]byte),
mmap: mmap,
munmap: munmap,
}
func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
return mapper.Mmap(fd, offset, length, prot, flags)
}
func Munmap(b []byte) (err error) {
return mapper.Munmap(b)
}
//sys Madvise(b []byte, advice int) (err error)
//sys Mprotect(b []byte, prot int) (err error)
//sys Mlock(b []byte) (err error)
//sys Mlockall(flags int) (err error)
//sys Msync(b []byte, flags int) (err error)
//sys Munlock(b []byte) (err error)
//sys Munlockall() (err error)
// Vmsplice splices user pages from a slice of Iovecs into a pipe specified by fd,
// using the specified flags.
func Vmsplice(fd int, iovs []Iovec, flags int) (int, error) {
var p unsafe.Pointer
if len(iovs) > 0 {
p = unsafe.Pointer(&iovs[0])
}
n, _, errno := Syscall6(SYS_VMSPLICE, uintptr(fd), uintptr(p), uintptr(len(iovs)), uintptr(flags), 0, 0)
if errno != 0 {
return 0, syscall.Errno(errno)
}
return int(n), nil
}
func isGroupMember(gid int) bool {
groups, err := Getgroups()
if err != nil {
return false
}
for _, g := range groups {
if g == gid {
return true
}
}
return false
}
//sys faccessat(dirfd int, path string, mode uint32) (err error)
//sys Faccessat2(dirfd int, path string, mode uint32, flags int) (err error)
func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
if flags == 0 {
return faccessat(dirfd, path, mode)
}
if err := Faccessat2(dirfd, path, mode, flags); err != ENOSYS && err != EPERM {
return err
}
// The Linux kernel faccessat system call does not take any flags.
// The glibc faccessat implements the flags itself; see
// https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/faccessat.c;hb=HEAD
// Because people naturally expect syscall.Faccessat to act
// like C faccessat, we do the same.
if flags & ^(AT_SYMLINK_NOFOLLOW|AT_EACCESS) != 0 {
return EINVAL
}
var st Stat_t
if err := Fstatat(dirfd, path, &st, flags&AT_SYMLINK_NOFOLLOW); err != nil {
return err
}
mode &= 7
if mode == 0 {
return nil
}
var uid int
if flags&AT_EACCESS != 0 {
uid = Geteuid()
} else {
uid = Getuid()
}
if uid == 0 {
if mode&1 == 0 {
// Root can read and write any file.
return nil
}
if st.Mode&0111 != 0 {
// Root can execute any file that anybody can execute.
return nil
}
return EACCES
}
var fmode uint32
if uint32(uid) == st.Uid {
fmode = (st.Mode >> 6) & 7
} else {
var gid int
if flags&AT_EACCESS != 0 {
gid = Getegid()
} else {
gid = Getgid()
}
if uint32(gid) == st.Gid || isGroupMember(gid) {
fmode = (st.Mode >> 3) & 7
} else {
fmode = st.Mode & 7
}
}
if fmode&mode == mode {
return nil
}
return EACCES
}
//sys nameToHandleAt(dirFD int, pathname string, fh *fileHandle, mountID *_C_int, flags int) (err error) = SYS_NAME_TO_HANDLE_AT
//sys openByHandleAt(mountFD int, fh *fileHandle, flags int) (fd int, err error) = SYS_OPEN_BY_HANDLE_AT
// fileHandle is the argument to nameToHandleAt and openByHandleAt. We
// originally tried to generate it via unix/linux/types.go with "type
// fileHandle C.struct_file_handle" but that generated empty structs
// for mips64 and mips64le. Instead, hard code it for now (it's the
// same everywhere else) until the mips64 generator issue is fixed.
type fileHandle struct {
Bytes uint32
Type int32
}
// FileHandle represents the C struct file_handle used by
// name_to_handle_at (see NameToHandleAt) and open_by_handle_at (see
// OpenByHandleAt).
type FileHandle struct {
*fileHandle
}
// NewFileHandle constructs a FileHandle.
func NewFileHandle(handleType int32, handle []byte) FileHandle {
const hdrSize = unsafe.Sizeof(fileHandle{})
buf := make([]byte, hdrSize+uintptr(len(handle)))
copy(buf[hdrSize:], handle)
fh := (*fileHandle)(unsafe.Pointer(&buf[0]))
fh.Type = handleType
fh.Bytes = uint32(len(handle))
return FileHandle{fh}
}
func (fh *FileHandle) Size() int { return int(fh.fileHandle.Bytes) }
func (fh *FileHandle) Type() int32 { return fh.fileHandle.Type }
func (fh *FileHandle) Bytes() []byte {
n := fh.Size()
if n == 0 {
return nil
}
return (*[1 << 30]byte)(unsafe.Pointer(uintptr(unsafe.Pointer(&fh.fileHandle.Type)) + 4))[:n:n]
}
// NameToHandleAt wraps the name_to_handle_at system call; it obtains
// a handle for a path name.
func NameToHandleAt(dirfd int, path string, flags int) (handle FileHandle, mountID int, err error) {
var mid _C_int
// Try first with a small buffer, assuming the handle will
// only be 32 bytes.
size := uint32(32 + unsafe.Sizeof(fileHandle{}))
didResize := false
for {
buf := make([]byte, size)
fh := (*fileHandle)(unsafe.Pointer(&buf[0]))
fh.Bytes = size - uint32(unsafe.Sizeof(fileHandle{}))
err = nameToHandleAt(dirfd, path, fh, &mid, flags)
if err == EOVERFLOW {
if didResize {
// We shouldn't need to resize more than once
return
}
didResize = true
size = fh.Bytes + uint32(unsafe.Sizeof(fileHandle{}))
continue
}
if err != nil {
return
}
return FileHandle{fh}, int(mid), nil
}
}
// OpenByHandleAt wraps the open_by_handle_at system call; it opens a
// file via a handle as previously returned by NameToHandleAt.
func OpenByHandleAt(mountFD int, handle FileHandle, flags int) (fd int, err error) {
return openByHandleAt(mountFD, handle.fileHandle, flags)
}
// Klogset wraps the sys_syslog system call; it sets console_loglevel to
// the value specified by arg and passes a dummy pointer to bufp.
func Klogset(typ int, arg int) (err error) {
var p unsafe.Pointer
_, _, errno := Syscall(SYS_SYSLOG, uintptr(typ), uintptr(p), uintptr(arg))
if errno != 0 {
return errnoErr(errno)
}
return nil
}
// RemoteIovec is Iovec with the pointer replaced with an integer.
// It is used for ProcessVMReadv and ProcessVMWritev, where the pointer
// refers to a location in a different process' address space, which
// would confuse the Go garbage collector.
type RemoteIovec struct {
Base uintptr
Len int
}
//sys ProcessVMReadv(pid int, localIov []Iovec, remoteIov []RemoteIovec, flags uint) (n int, err error) = SYS_PROCESS_VM_READV
//sys ProcessVMWritev(pid int, localIov []Iovec, remoteIov []RemoteIovec, flags uint) (n int, err error) = SYS_PROCESS_VM_WRITEV
/*
* Unimplemented
*/
// AfsSyscall
// Alarm
// ArchPrctl
// Brk
// ClockNanosleep
// ClockSettime
// Clone
// EpollCtlOld
// EpollPwait
// EpollWaitOld
// Execve
// Fork
// Futex
// GetKernelSyms
// GetMempolicy
// GetRobustList
// GetThreadArea
// Getitimer
// Getpmsg
// IoCancel
// IoDestroy
// IoGetevents
// IoSetup
// IoSubmit
// IoprioGet
// IoprioSet
// KexecLoad
// LookupDcookie
// Mbind
// MigratePages
// Mincore
// ModifyLdt
// Mount
// MovePages
// MqGetsetattr
// MqNotify
// MqOpen
// MqTimedreceive
// MqTimedsend
// MqUnlink
// Mremap
// Msgctl
// Msgget
// Msgrcv
// Msgsnd
// Nfsservctl
// Personality
// Pselect6
// Ptrace
// Putpmsg
// Quotactl
// Readahead
// Readv
// RemapFilePages
// RestartSyscall
// RtSigaction
// RtSigpending
// RtSigprocmask
// RtSigqueueinfo
// RtSigreturn
// RtSigsuspend
// RtSigtimedwait
// SchedGetPriorityMax
// SchedGetPriorityMin
// SchedGetparam
// SchedGetscheduler
// SchedRrGetInterval
// SchedSetparam
// SchedYield
// Security
// Semctl
// Semget
// Semop
// Semtimedop
// SetMempolicy
// SetRobustList
// SetThreadArea
// SetTidAddress
// Shmat
// Shmctl
// Shmdt
// Shmget
// Sigaltstack
// Swapoff
// Swapon
// Sysfs
// TimerCreate
// TimerDelete
// TimerGetoverrun
// TimerGettime
// TimerSettime
// Tkill (obsolete)
// Tuxcall
// Umount2
// Uselib
// Utimensat
// Vfork
// Vhangup
// Vserver
// Waitid
// _Sysctl