syscall_unix.go - usb-ks - USB Killswitch

syscall_unix.go (12454B)
      1 // Copyright 2009 The Go Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style
      3 // license that can be found in the LICENSE file.
      4 
      5 //go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
      6 // +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
      7 
      8 package unix
      9 
     10 import (
     11 	"bytes"
     12 	"sort"
     13 	"sync"
     14 	"syscall"
     15 	"unsafe"
     16 
     17 	"golang.org/x/sys/internal/unsafeheader"
     18 )
     19 
     20 var (
     21 	Stdin  = 0
     22 	Stdout = 1
     23 	Stderr = 2
     24 )
     25 
     26 // Do the interface allocations only once for common
     27 // Errno values.
     28 var (
     29 	errEAGAIN error = syscall.EAGAIN
     30 	errEINVAL error = syscall.EINVAL
     31 	errENOENT error = syscall.ENOENT
     32 )
     33 
     34 var (
     35 	signalNameMapOnce sync.Once
     36 	signalNameMap     map[string]syscall.Signal
     37 )
     38 
     39 // errnoErr returns common boxed Errno values, to prevent
     40 // allocations at runtime.
     41 func errnoErr(e syscall.Errno) error {
     42 	switch e {
     43 	case 0:
     44 		return nil
     45 	case EAGAIN:
     46 		return errEAGAIN
     47 	case EINVAL:
     48 		return errEINVAL
     49 	case ENOENT:
     50 		return errENOENT
     51 	}
     52 	return e
     53 }
     54 
     55 // ErrnoName returns the error name for error number e.
     56 func ErrnoName(e syscall.Errno) string {
     57 	i := sort.Search(len(errorList), func(i int) bool {
     58 		return errorList[i].num >= e
     59 	})
     60 	if i < len(errorList) && errorList[i].num == e {
     61 		return errorList[i].name
     62 	}
     63 	return ""
     64 }
     65 
     66 // SignalName returns the signal name for signal number s.
     67 func SignalName(s syscall.Signal) string {
     68 	i := sort.Search(len(signalList), func(i int) bool {
     69 		return signalList[i].num >= s
     70 	})
     71 	if i < len(signalList) && signalList[i].num == s {
     72 		return signalList[i].name
     73 	}
     74 	return ""
     75 }
     76 
     77 // SignalNum returns the syscall.Signal for signal named s,
     78 // or 0 if a signal with such name is not found.
     79 // The signal name should start with "SIG".
     80 func SignalNum(s string) syscall.Signal {
     81 	signalNameMapOnce.Do(func() {
     82 		signalNameMap = make(map[string]syscall.Signal, len(signalList))
     83 		for _, signal := range signalList {
     84 			signalNameMap[signal.name] = signal.num
     85 		}
     86 	})
     87 	return signalNameMap[s]
     88 }
     89 
     90 // clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte.
     91 func clen(n []byte) int {
     92 	i := bytes.IndexByte(n, 0)
     93 	if i == -1 {
     94 		i = len(n)
     95 	}
     96 	return i
     97 }
     98 
     99 // Mmap manager, for use by operating system-specific implementations.
    100 
    101 type mmapper struct {
    102 	sync.Mutex
    103 	active map[*byte][]byte // active mappings; key is last byte in mapping
    104 	mmap   func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error)
    105 	munmap func(addr uintptr, length uintptr) error
    106 }
    107 
    108 func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
    109 	if length <= 0 {
    110 		return nil, EINVAL
    111 	}
    112 
    113 	// Map the requested memory.
    114 	addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset)
    115 	if errno != nil {
    116 		return nil, errno
    117 	}
    118 
    119 	// Use unsafe to convert addr into a []byte.
    120 	var b []byte
    121 	hdr := (*unsafeheader.Slice)(unsafe.Pointer(&b))
    122 	hdr.Data = unsafe.Pointer(addr)
    123 	hdr.Cap = length
    124 	hdr.Len = length
    125 
    126 	// Register mapping in m and return it.
    127 	p := &b[cap(b)-1]
    128 	m.Lock()
    129 	defer m.Unlock()
    130 	m.active[p] = b
    131 	return b, nil
    132 }
    133 
    134 func (m *mmapper) Munmap(data []byte) (err error) {
    135 	if len(data) == 0 || len(data) != cap(data) {
    136 		return EINVAL
    137 	}
    138 
    139 	// Find the base of the mapping.
    140 	p := &data[cap(data)-1]
    141 	m.Lock()
    142 	defer m.Unlock()
    143 	b := m.active[p]
    144 	if b == nil || &b[0] != &data[0] {
    145 		return EINVAL
    146 	}
    147 
    148 	// Unmap the memory and update m.
    149 	if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil {
    150 		return errno
    151 	}
    152 	delete(m.active, p)
    153 	return nil
    154 }
    155 
    156 func Read(fd int, p []byte) (n int, err error) {
    157 	n, err = read(fd, p)
    158 	if raceenabled {
    159 		if n > 0 {
    160 			raceWriteRange(unsafe.Pointer(&p[0]), n)
    161 		}
    162 		if err == nil {
    163 			raceAcquire(unsafe.Pointer(&ioSync))
    164 		}
    165 	}
    166 	return
    167 }
    168 
    169 func Write(fd int, p []byte) (n int, err error) {
    170 	if raceenabled {
    171 		raceReleaseMerge(unsafe.Pointer(&ioSync))
    172 	}
    173 	n, err = write(fd, p)
    174 	if raceenabled && n > 0 {
    175 		raceReadRange(unsafe.Pointer(&p[0]), n)
    176 	}
    177 	return
    178 }
    179 
    180 func Pread(fd int, p []byte, offset int64) (n int, err error) {
    181 	n, err = pread(fd, p, offset)
    182 	if raceenabled {
    183 		if n > 0 {
    184 			raceWriteRange(unsafe.Pointer(&p[0]), n)
    185 		}
    186 		if err == nil {
    187 			raceAcquire(unsafe.Pointer(&ioSync))
    188 		}
    189 	}
    190 	return
    191 }
    192 
    193 func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
    194 	if raceenabled {
    195 		raceReleaseMerge(unsafe.Pointer(&ioSync))
    196 	}
    197 	n, err = pwrite(fd, p, offset)
    198 	if raceenabled && n > 0 {
    199 		raceReadRange(unsafe.Pointer(&p[0]), n)
    200 	}
    201 	return
    202 }
    203 
    204 // For testing: clients can set this flag to force
    205 // creation of IPv6 sockets to return EAFNOSUPPORT.
    206 var SocketDisableIPv6 bool
    207 
    208 // Sockaddr represents a socket address.
    209 type Sockaddr interface {
    210 	sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs
    211 }
    212 
    213 // SockaddrInet4 implements the Sockaddr interface for AF_INET type sockets.
    214 type SockaddrInet4 struct {
    215 	Port int
    216 	Addr [4]byte
    217 	raw  RawSockaddrInet4
    218 }
    219 
    220 // SockaddrInet6 implements the Sockaddr interface for AF_INET6 type sockets.
    221 type SockaddrInet6 struct {
    222 	Port   int
    223 	ZoneId uint32
    224 	Addr   [16]byte
    225 	raw    RawSockaddrInet6
    226 }
    227 
    228 // SockaddrUnix implements the Sockaddr interface for AF_UNIX type sockets.
    229 type SockaddrUnix struct {
    230 	Name string
    231 	raw  RawSockaddrUnix
    232 }
    233 
    234 func Bind(fd int, sa Sockaddr) (err error) {
    235 	ptr, n, err := sa.sockaddr()
    236 	if err != nil {
    237 		return err
    238 	}
    239 	return bind(fd, ptr, n)
    240 }
    241 
    242 func Connect(fd int, sa Sockaddr) (err error) {
    243 	ptr, n, err := sa.sockaddr()
    244 	if err != nil {
    245 		return err
    246 	}
    247 	return connect(fd, ptr, n)
    248 }
    249 
    250 func Getpeername(fd int) (sa Sockaddr, err error) {
    251 	var rsa RawSockaddrAny
    252 	var len _Socklen = SizeofSockaddrAny
    253 	if err = getpeername(fd, &rsa, &len); err != nil {
    254 		return
    255 	}
    256 	return anyToSockaddr(fd, &rsa)
    257 }
    258 
    259 func GetsockoptByte(fd, level, opt int) (value byte, err error) {
    260 	var n byte
    261 	vallen := _Socklen(1)
    262 	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
    263 	return n, err
    264 }
    265 
    266 func GetsockoptInt(fd, level, opt int) (value int, err error) {
    267 	var n int32
    268 	vallen := _Socklen(4)
    269 	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
    270 	return int(n), err
    271 }
    272 
    273 func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
    274 	vallen := _Socklen(4)
    275 	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
    276 	return value, err
    277 }
    278 
    279 func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
    280 	var value IPMreq
    281 	vallen := _Socklen(SizeofIPMreq)
    282 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
    283 	return &value, err
    284 }
    285 
    286 func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
    287 	var value IPv6Mreq
    288 	vallen := _Socklen(SizeofIPv6Mreq)
    289 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
    290 	return &value, err
    291 }
    292 
    293 func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
    294 	var value IPv6MTUInfo
    295 	vallen := _Socklen(SizeofIPv6MTUInfo)
    296 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
    297 	return &value, err
    298 }
    299 
    300 func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
    301 	var value ICMPv6Filter
    302 	vallen := _Socklen(SizeofICMPv6Filter)
    303 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
    304 	return &value, err
    305 }
    306 
    307 func GetsockoptLinger(fd, level, opt int) (*Linger, error) {
    308 	var linger Linger
    309 	vallen := _Socklen(SizeofLinger)
    310 	err := getsockopt(fd, level, opt, unsafe.Pointer(&linger), &vallen)
    311 	return &linger, err
    312 }
    313 
    314 func GetsockoptTimeval(fd, level, opt int) (*Timeval, error) {
    315 	var tv Timeval
    316 	vallen := _Socklen(unsafe.Sizeof(tv))
    317 	err := getsockopt(fd, level, opt, unsafe.Pointer(&tv), &vallen)
    318 	return &tv, err
    319 }
    320 
    321 func GetsockoptUint64(fd, level, opt int) (value uint64, err error) {
    322 	var n uint64
    323 	vallen := _Socklen(8)
    324 	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
    325 	return n, err
    326 }
    327 
    328 func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) {
    329 	var rsa RawSockaddrAny
    330 	var len _Socklen = SizeofSockaddrAny
    331 	if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil {
    332 		return
    333 	}
    334 	if rsa.Addr.Family != AF_UNSPEC {
    335 		from, err = anyToSockaddr(fd, &rsa)
    336 	}
    337 	return
    338 }
    339 
    340 func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
    341 	var rsa RawSockaddrAny
    342 	n, oobn, recvflags, err = recvmsgRaw(fd, p, oob, flags, &rsa)
    343 	// source address is only specified if the socket is unconnected
    344 	if rsa.Addr.Family != AF_UNSPEC {
    345 		from, err = anyToSockaddr(fd, &rsa)
    346 	}
    347 	return
    348 }
    349 
    350 func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
    351 	_, err = SendmsgN(fd, p, oob, to, flags)
    352 	return
    353 }
    354 
    355 func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
    356 	var ptr unsafe.Pointer
    357 	var salen _Socklen
    358 	if to != nil {
    359 		ptr, salen, err = to.sockaddr()
    360 		if err != nil {
    361 			return 0, err
    362 		}
    363 	}
    364 	return sendmsgN(fd, p, oob, ptr, salen, flags)
    365 }
    366 
    367 func Send(s int, buf []byte, flags int) (err error) {
    368 	return sendto(s, buf, flags, nil, 0)
    369 }
    370 
    371 func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
    372 	ptr, n, err := to.sockaddr()
    373 	if err != nil {
    374 		return err
    375 	}
    376 	return sendto(fd, p, flags, ptr, n)
    377 }
    378 
    379 func SetsockoptByte(fd, level, opt int, value byte) (err error) {
    380 	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1)
    381 }
    382 
    383 func SetsockoptInt(fd, level, opt int, value int) (err error) {
    384 	var n = int32(value)
    385 	return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4)
    386 }
    387 
    388 func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) {
    389 	return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4)
    390 }
    391 
    392 func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) {
    393 	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq)
    394 }
    395 
    396 func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) {
    397 	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq)
    398 }
    399 
    400 func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error {
    401 	return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter)
    402 }
    403 
    404 func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) {
    405 	return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger)
    406 }
    407 
    408 func SetsockoptString(fd, level, opt int, s string) (err error) {
    409 	var p unsafe.Pointer
    410 	if len(s) > 0 {
    411 		p = unsafe.Pointer(&[]byte(s)[0])
    412 	}
    413 	return setsockopt(fd, level, opt, p, uintptr(len(s)))
    414 }
    415 
    416 func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) {
    417 	return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv))
    418 }
    419 
    420 func SetsockoptUint64(fd, level, opt int, value uint64) (err error) {
    421 	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 8)
    422 }
    423 
    424 func Socket(domain, typ, proto int) (fd int, err error) {
    425 	if domain == AF_INET6 && SocketDisableIPv6 {
    426 		return -1, EAFNOSUPPORT
    427 	}
    428 	fd, err = socket(domain, typ, proto)
    429 	return
    430 }
    431 
    432 func Socketpair(domain, typ, proto int) (fd [2]int, err error) {
    433 	var fdx [2]int32
    434 	err = socketpair(domain, typ, proto, &fdx)
    435 	if err == nil {
    436 		fd[0] = int(fdx[0])
    437 		fd[1] = int(fdx[1])
    438 	}
    439 	return
    440 }
    441 
    442 var ioSync int64
    443 
    444 func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) }
    445 
    446 func SetNonblock(fd int, nonblocking bool) (err error) {
    447 	flag, err := fcntl(fd, F_GETFL, 0)
    448 	if err != nil {
    449 		return err
    450 	}
    451 	if nonblocking {
    452 		flag |= O_NONBLOCK
    453 	} else {
    454 		flag &= ^O_NONBLOCK
    455 	}
    456 	_, err = fcntl(fd, F_SETFL, flag)
    457 	return err
    458 }
    459 
    460 // Exec calls execve(2), which replaces the calling executable in the process
    461 // tree. argv0 should be the full path to an executable ("/bin/ls") and the
    462 // executable name should also be the first argument in argv (["ls", "-l"]).
    463 // envv are the environment variables that should be passed to the new
    464 // process (["USER=go", "PWD=/tmp"]).
    465 func Exec(argv0 string, argv []string, envv []string) error {
    466 	return syscall.Exec(argv0, argv, envv)
    467 }
    468 
    469 // Lutimes sets the access and modification times tv on path. If path refers to
    470 // a symlink, it is not dereferenced and the timestamps are set on the symlink.
    471 // If tv is nil, the access and modification times are set to the current time.
    472 // Otherwise tv must contain exactly 2 elements, with access time as the first
    473 // element and modification time as the second element.
    474 func Lutimes(path string, tv []Timeval) error {
    475 	if tv == nil {
    476 		return UtimesNanoAt(AT_FDCWD, path, nil, AT_SYMLINK_NOFOLLOW)
    477 	}
    478 	if len(tv) != 2 {
    479 		return EINVAL
    480 	}
    481 	ts := []Timespec{
    482 		NsecToTimespec(TimevalToNsec(tv[0])),
    483 		NsecToTimespec(TimevalToNsec(tv[1])),
    484 	}
    485 	return UtimesNanoAt(AT_FDCWD, path, ts, AT_SYMLINK_NOFOLLOW)
    486 }
	usb-ks USB Killswitch
	git clone git://git.laack.co/usb-ks.git
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