| // 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 syscall |
| |
| import ( |
| "internal/itoa" |
| "unsafe" |
| ) |
| |
| func rawSyscallNoError(trap, a1, a2, a3 uintptr) (r1, r2 uintptr) |
| |
| /* |
| * 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) |
| } |
| |
| 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) |
| |
| func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) { |
| if flags & ^(_AT_SYMLINK_NOFOLLOW|_AT_EACCESS) != 0 { |
| return EINVAL |
| } |
| |
| // 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 == 0 { |
| return faccessat(dirfd, path, mode) |
| } |
| |
| 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 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 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 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 Unlinkat(dirfd int, path string) error { |
| return unlinkat(dirfd, path, 0) |
| } |
| |
| func Utimes(path string, tv []Timeval) (err error) { |
| if len(tv) != 2 { |
| return EINVAL |
| } |
| return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) |
| } |
| |
| //sys utimensat(dirfd int, path string, times *[2]Timespec, flag int) (err error) |
| |
| func UtimesNano(path string, ts []Timespec) (err error) { |
| 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].Sec = ts[i].Sec |
| tv[i].Usec = ts[i].Nsec / 1000 |
| } |
| return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) |
| } |
| |
| func Futimesat(dirfd int, path string, tv []Timeval) (err error) { |
| 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.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 |
| } |
| |
| var cgo_libc_setgroups unsafe.Pointer // non-nil if cgo linked. |
| |
| func Setgroups(gids []int) (err error) { |
| n := uintptr(len(gids)) |
| if n == 0 { |
| if cgo_libc_setgroups == nil { |
| if _, _, e1 := AllThreadsSyscall(_SYS_setgroups, 0, 0, 0); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| return |
| } |
| if ret := cgocaller(cgo_libc_setgroups, 0, 0); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| a := make([]_Gid_t, len(gids)) |
| for i, v := range gids { |
| a[i] = _Gid_t(v) |
| } |
| if cgo_libc_setgroups == nil { |
| if _, _, e1 := AllThreadsSyscall(_SYS_setgroups, n, uintptr(unsafe.Pointer(&a[0])), 0); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| return |
| } |
| if ret := cgocaller(cgo_libc_setgroups, n, uintptr(unsafe.Pointer(&a[0]))); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| 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() Signal { |
| if !w.Signaled() { |
| return -1 |
| } |
| return Signal(w & mask) |
| } |
| |
| func (w WaitStatus) StopSignal() Signal { |
| if !w.Stopped() { |
| return -1 |
| } |
| return 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) (err error) { |
| return Mknod(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 |
| } |
| if n == len(sa.raw.Path) && name[0] != '@' { |
| 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 |
| } |
| |
| 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 |
| } |
| |
| 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 |
| } |
| |
| func anyToSockaddr(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: |
| 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: |
| 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 |
| } |
| 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(&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(&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(&rsa) |
| } |
| |
| func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) { |
| vallen := _Socklen(4) |
| err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen) |
| return value, err |
| } |
| |
| func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) { |
| var value IPMreq |
| vallen := _Socklen(SizeofIPMreq) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) |
| return &value, err |
| } |
| |
| 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 GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) { |
| var value IPv6Mreq |
| vallen := _Socklen(SizeofIPv6Mreq) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) |
| return &value, err |
| } |
| |
| func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) { |
| var value IPv6MTUInfo |
| vallen := _Socklen(SizeofIPv6MTUInfo) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) |
| return &value, err |
| } |
| |
| func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) { |
| var value ICMPv6Filter |
| vallen := _Socklen(SizeofICMPv6Filter) |
| 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 SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) { |
| return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq)) |
| } |
| |
| 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(&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 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 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 PtraceAttach(pid int) (err error) { return ptrace(PTRACE_ATTACH, 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 ReadDirent(fd int, buf []byte) (n int, err error) { |
| return Getdents(fd, buf) |
| } |
| |
| 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) |
| } |
| |
| // Sendto |
| // Recvfrom |
| // Socketpair |
| |
| /* |
| * Direct access |
| */ |
| //sys Acct(path string) (err error) |
| //sys Adjtimex(buf *Timex) (state int, err error) |
| //sys Chdir(path string) (err error) |
| //sys Chroot(path string) (err error) |
| //sys Close(fd int) (err error) |
| //sys Dup(oldfd int) (fd int, err error) |
| //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 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 fcntl(fd int, cmd int, arg int) (val int, err error) |
| //sys Fdatasync(fd int) (err error) |
| //sys Flock(fd int, how 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) |
| //sysnb Getrusage(who int, rusage *Rusage) (err error) |
| //sysnb Gettid() (tid int) |
| //sys Getxattr(path string, attr string, dest []byte) (sz int, 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 Signal) (err error) |
| //sys Klogctl(typ int, buf []byte) (n int, err error) = SYS_SYSLOG |
| //sys Listxattr(path string, dest []byte) (sz 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 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 read(fd int, p []byte) (n int, err error) |
| //sys Removexattr(path string, attr string) (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) |
| |
| // allThreadsCaller holds the input and output state for performing a |
| // allThreadsSyscall that needs to synchronize all OS thread state. Linux |
| // generally does not always support this natively, so we have to |
| // manipulate the runtime to fix things up. |
| type allThreadsCaller struct { |
| // arguments |
| trap, a1, a2, a3, a4, a5, a6 uintptr |
| |
| // return values (only set by 0th invocation) |
| r1, r2 uintptr |
| |
| // err is the error code |
| err Errno |
| } |
| |
| // doSyscall is a callback for executing a syscall on the current m |
| // (OS thread). |
| //go:nosplit |
| //go:norace |
| func (pc *allThreadsCaller) doSyscall(initial bool) bool { |
| r1, r2, err := RawSyscall(pc.trap, pc.a1, pc.a2, pc.a3) |
| if initial { |
| pc.r1 = r1 |
| pc.r2 = r2 |
| pc.err = err |
| } else if pc.r1 != r1 || (archHonorsR2 && pc.r2 != r2) || pc.err != err { |
| print("trap:", pc.trap, ", a123=[", pc.a1, ",", pc.a2, ",", pc.a3, "]\n") |
| print("results: got {r1=", r1, ",r2=", r2, ",err=", err, "}, want {r1=", pc.r1, ",r2=", pc.r2, ",r3=", pc.err, "}\n") |
| panic("AllThreadsSyscall results differ between threads; runtime corrupted") |
| } |
| return err == 0 |
| } |
| |
| // doSyscall6 is a callback for executing a syscall6 on the current m |
| // (OS thread). |
| //go:nosplit |
| //go:norace |
| func (pc *allThreadsCaller) doSyscall6(initial bool) bool { |
| r1, r2, err := RawSyscall6(pc.trap, pc.a1, pc.a2, pc.a3, pc.a4, pc.a5, pc.a6) |
| if initial { |
| pc.r1 = r1 |
| pc.r2 = r2 |
| pc.err = err |
| } else if pc.r1 != r1 || (archHonorsR2 && pc.r2 != r2) || pc.err != err { |
| print("trap:", pc.trap, ", a123456=[", pc.a1, ",", pc.a2, ",", pc.a3, ",", pc.a4, ",", pc.a5, ",", pc.a6, "]\n") |
| print("results: got {r1=", r1, ",r2=", r2, ",err=", err, "}, want {r1=", pc.r1, ",r2=", pc.r2, ",r3=", pc.err, "}\n") |
| panic("AllThreadsSyscall6 results differ between threads; runtime corrupted") |
| } |
| return err == 0 |
| } |
| |
| // Provided by runtime.syscall_runtime_doAllThreadsSyscall which |
| // serializes the world and invokes the fn on each OS thread (what the |
| // runtime refers to as m's). Once this function returns, all threads |
| // are in sync. |
| func runtime_doAllThreadsSyscall(fn func(bool) bool) |
| |
| // AllThreadsSyscall performs a syscall on each OS thread of the Go |
| // runtime. It first invokes the syscall on one thread. Should that |
| // invocation fail, it returns immediately with the error status. |
| // Otherwise, it invokes the syscall on all of the remaining threads |
| // in parallel. It will terminate the program if it observes any |
| // invoked syscall's return value differs from that of the first |
| // invocation. |
| // |
| // AllThreadsSyscall is intended for emulating simultaneous |
| // process-wide state changes that require consistently modifying |
| // per-thread state of the Go runtime. |
| // |
| // AllThreadsSyscall is unaware of any threads that are launched |
| // explicitly by cgo linked code, so the function always returns |
| // ENOTSUP in binaries that use cgo. |
| //go:uintptrescapes |
| func AllThreadsSyscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err Errno) { |
| if cgo_libc_setegid != nil { |
| return minus1, minus1, ENOTSUP |
| } |
| pc := &allThreadsCaller{ |
| trap: trap, |
| a1: a1, |
| a2: a2, |
| a3: a3, |
| } |
| runtime_doAllThreadsSyscall(pc.doSyscall) |
| r1 = pc.r1 |
| r2 = pc.r2 |
| err = pc.err |
| return |
| } |
| |
| // AllThreadsSyscall6 is like AllThreadsSyscall, but extended to six |
| // arguments. |
| //go:uintptrescapes |
| func AllThreadsSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err Errno) { |
| if cgo_libc_setegid != nil { |
| return minus1, minus1, ENOTSUP |
| } |
| pc := &allThreadsCaller{ |
| trap: trap, |
| a1: a1, |
| a2: a2, |
| a3: a3, |
| a4: a4, |
| a5: a5, |
| a6: a6, |
| } |
| runtime_doAllThreadsSyscall(pc.doSyscall6) |
| r1 = pc.r1 |
| r2 = pc.r2 |
| err = pc.err |
| return |
| } |
| |
| // linked by runtime.cgocall.go |
| //go:uintptrescapes |
| func cgocaller(unsafe.Pointer, ...uintptr) uintptr |
| |
| var cgo_libc_setegid unsafe.Pointer // non-nil if cgo linked. |
| |
| const minus1 = ^uintptr(0) |
| |
| func Setegid(egid int) (err error) { |
| if cgo_libc_setegid == nil { |
| if _, _, e1 := AllThreadsSyscall(SYS_SETRESGID, minus1, uintptr(egid), minus1); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| } else if ret := cgocaller(cgo_libc_setegid, uintptr(egid)); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| var cgo_libc_seteuid unsafe.Pointer // non-nil if cgo linked. |
| |
| func Seteuid(euid int) (err error) { |
| if cgo_libc_seteuid == nil { |
| if _, _, e1 := AllThreadsSyscall(SYS_SETRESUID, minus1, uintptr(euid), minus1); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| } else if ret := cgocaller(cgo_libc_seteuid, uintptr(euid)); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| var cgo_libc_setgid unsafe.Pointer // non-nil if cgo linked. |
| |
| func Setgid(gid int) (err error) { |
| if cgo_libc_setgid == nil { |
| if _, _, e1 := AllThreadsSyscall(sys_SETGID, uintptr(gid), 0, 0); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| } else if ret := cgocaller(cgo_libc_setgid, uintptr(gid)); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| var cgo_libc_setregid unsafe.Pointer // non-nil if cgo linked. |
| |
| func Setregid(rgid, egid int) (err error) { |
| if cgo_libc_setregid == nil { |
| if _, _, e1 := AllThreadsSyscall(sys_SETREGID, uintptr(rgid), uintptr(egid), 0); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| } else if ret := cgocaller(cgo_libc_setregid, uintptr(rgid), uintptr(egid)); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| var cgo_libc_setresgid unsafe.Pointer // non-nil if cgo linked. |
| |
| func Setresgid(rgid, egid, sgid int) (err error) { |
| if cgo_libc_setresgid == nil { |
| if _, _, e1 := AllThreadsSyscall(sys_SETRESGID, uintptr(rgid), uintptr(egid), uintptr(sgid)); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| } else if ret := cgocaller(cgo_libc_setresgid, uintptr(rgid), uintptr(egid), uintptr(sgid)); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| var cgo_libc_setresuid unsafe.Pointer // non-nil if cgo linked. |
| |
| func Setresuid(ruid, euid, suid int) (err error) { |
| if cgo_libc_setresuid == nil { |
| if _, _, e1 := AllThreadsSyscall(sys_SETRESUID, uintptr(ruid), uintptr(euid), uintptr(suid)); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| } else if ret := cgocaller(cgo_libc_setresuid, uintptr(ruid), uintptr(euid), uintptr(suid)); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| var cgo_libc_setreuid unsafe.Pointer // non-nil if cgo linked. |
| |
| func Setreuid(ruid, euid int) (err error) { |
| if cgo_libc_setreuid == nil { |
| if _, _, e1 := AllThreadsSyscall(sys_SETREUID, uintptr(ruid), uintptr(euid), 0); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| } else if ret := cgocaller(cgo_libc_setreuid, uintptr(ruid), uintptr(euid)); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| var cgo_libc_setuid unsafe.Pointer // non-nil if cgo linked. |
| |
| func Setuid(uid int) (err error) { |
| if cgo_libc_setuid == nil { |
| if _, _, e1 := AllThreadsSyscall(sys_SETUID, uintptr(uid), 0, 0); e1 != 0 { |
| err = errnoErr(e1) |
| } |
| } else if ret := cgocaller(cgo_libc_setuid, uintptr(uid)); ret != 0 { |
| err = errnoErr(Errno(ret)) |
| } |
| return |
| } |
| |
| //sys Setpriority(which int, who int, prio int) (err error) |
| //sys Setxattr(path string, attr string, data []byte, flags int) (err error) |
| //sys Sync() |
| //sysnb Sysinfo(info *Sysinfo_t) (err error) |
| //sys Tee(rfd int, wfd int, len int, flags int) (n int64, err error) |
| //sysnb Tgkill(tgid int, tid int, sig 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 |
| |
| // 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 Munlock(b []byte) (err error) |
| //sys Mlockall(flags int) (err error) |
| //sys Munlockall() (err error) |
