github.com/c12o16h1/go/src@v0.0.0-20200114212001-5a151c0f00ed/syscall/syscall_linux.go (about) 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 // Linux system calls. 6 // This file is compiled as ordinary Go code, 7 // but it is also input to mksyscall, 8 // which parses the //sys lines and generates system call stubs. 9 // Note that sometimes we use a lowercase //sys name and 10 // wrap it in our own nicer implementation. 11 12 package syscall 13 14 import "unsafe" 15 16 func rawSyscallNoError(trap, a1, a2, a3 uintptr) (r1, r2 uintptr) 17 18 /* 19 * Wrapped 20 */ 21 22 func Access(path string, mode uint32) (err error) { 23 return Faccessat(_AT_FDCWD, path, mode, 0) 24 } 25 26 func Chmod(path string, mode uint32) (err error) { 27 return Fchmodat(_AT_FDCWD, path, mode, 0) 28 } 29 30 func Chown(path string, uid int, gid int) (err error) { 31 return Fchownat(_AT_FDCWD, path, uid, gid, 0) 32 } 33 34 func Creat(path string, mode uint32) (fd int, err error) { 35 return Open(path, O_CREAT|O_WRONLY|O_TRUNC, mode) 36 } 37 38 //sys faccessat(dirfd int, path string, mode uint32) (err error) 39 40 func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) { 41 if flags & ^(_AT_SYMLINK_NOFOLLOW|_AT_EACCESS) != 0 { 42 return EINVAL 43 } 44 45 // The Linux kernel faccessat system call does not take any flags. 46 // The glibc faccessat implements the flags itself; see 47 // https://sourceware.org/git/?p=glibc.git;a=blob;f=sysdeps/unix/sysv/linux/faccessat.c;hb=HEAD 48 // Because people naturally expect syscall.Faccessat to act 49 // like C faccessat, we do the same. 50 51 if flags == 0 { 52 return faccessat(dirfd, path, mode) 53 } 54 55 var st Stat_t 56 if err := fstatat(dirfd, path, &st, flags&_AT_SYMLINK_NOFOLLOW); err != nil { 57 return err 58 } 59 60 mode &= 7 61 if mode == 0 { 62 return nil 63 } 64 65 var uid int 66 if flags&_AT_EACCESS != 0 { 67 uid = Geteuid() 68 } else { 69 uid = Getuid() 70 } 71 72 if uid == 0 { 73 if mode&1 == 0 { 74 // Root can read and write any file. 75 return nil 76 } 77 if st.Mode&0111 != 0 { 78 // Root can execute any file that anybody can execute. 79 return nil 80 } 81 return EACCES 82 } 83 84 var fmode uint32 85 if uint32(uid) == st.Uid { 86 fmode = (st.Mode >> 6) & 7 87 } else { 88 var gid int 89 if flags&_AT_EACCESS != 0 { 90 gid = Getegid() 91 } else { 92 gid = Getgid() 93 } 94 95 if uint32(gid) == st.Gid { 96 fmode = (st.Mode >> 3) & 7 97 } else { 98 fmode = st.Mode & 7 99 } 100 } 101 102 if fmode&mode == mode { 103 return nil 104 } 105 106 return EACCES 107 } 108 109 //sys fchmodat(dirfd int, path string, mode uint32) (err error) 110 111 func Fchmodat(dirfd int, path string, mode uint32, flags int) (err error) { 112 // Linux fchmodat doesn't support the flags parameter. Mimick glibc's behavior 113 // and check the flags. Otherwise the mode would be applied to the symlink 114 // destination which is not what the user expects. 115 if flags&^_AT_SYMLINK_NOFOLLOW != 0 { 116 return EINVAL 117 } else if flags&_AT_SYMLINK_NOFOLLOW != 0 { 118 return EOPNOTSUPP 119 } 120 return fchmodat(dirfd, path, mode) 121 } 122 123 //sys linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error) 124 125 func Link(oldpath string, newpath string) (err error) { 126 return linkat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath, 0) 127 } 128 129 func Mkdir(path string, mode uint32) (err error) { 130 return Mkdirat(_AT_FDCWD, path, mode) 131 } 132 133 func Mknod(path string, mode uint32, dev int) (err error) { 134 return Mknodat(_AT_FDCWD, path, mode, dev) 135 } 136 137 func Open(path string, mode int, perm uint32) (fd int, err error) { 138 return openat(_AT_FDCWD, path, mode|O_LARGEFILE, perm) 139 } 140 141 //sys openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) 142 143 func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) { 144 return openat(dirfd, path, flags|O_LARGEFILE, mode) 145 } 146 147 //sys readlinkat(dirfd int, path string, buf []byte) (n int, err error) 148 149 func Readlink(path string, buf []byte) (n int, err error) { 150 return readlinkat(_AT_FDCWD, path, buf) 151 } 152 153 func Rename(oldpath string, newpath string) (err error) { 154 return Renameat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath) 155 } 156 157 func Rmdir(path string) error { 158 return unlinkat(_AT_FDCWD, path, _AT_REMOVEDIR) 159 } 160 161 //sys symlinkat(oldpath string, newdirfd int, newpath string) (err error) 162 163 func Symlink(oldpath string, newpath string) (err error) { 164 return symlinkat(oldpath, _AT_FDCWD, newpath) 165 } 166 167 func Unlink(path string) error { 168 return unlinkat(_AT_FDCWD, path, 0) 169 } 170 171 //sys unlinkat(dirfd int, path string, flags int) (err error) 172 173 func Unlinkat(dirfd int, path string) error { 174 return unlinkat(dirfd, path, 0) 175 } 176 177 func Utimes(path string, tv []Timeval) (err error) { 178 if len(tv) != 2 { 179 return EINVAL 180 } 181 return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) 182 } 183 184 //sys utimensat(dirfd int, path string, times *[2]Timespec, flag int) (err error) 185 186 func UtimesNano(path string, ts []Timespec) (err error) { 187 if len(ts) != 2 { 188 return EINVAL 189 } 190 err = utimensat(_AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0) 191 if err != ENOSYS { 192 return err 193 } 194 // If the utimensat syscall isn't available (utimensat was added to Linux 195 // in 2.6.22, Released, 8 July 2007) then fall back to utimes 196 var tv [2]Timeval 197 for i := 0; i < 2; i++ { 198 tv[i].Sec = ts[i].Sec 199 tv[i].Usec = ts[i].Nsec / 1000 200 } 201 return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) 202 } 203 204 func Futimesat(dirfd int, path string, tv []Timeval) (err error) { 205 if len(tv) != 2 { 206 return EINVAL 207 } 208 return futimesat(dirfd, path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) 209 } 210 211 func Futimes(fd int, tv []Timeval) (err error) { 212 // Believe it or not, this is the best we can do on Linux 213 // (and is what glibc does). 214 return Utimes("/proc/self/fd/"+itoa(fd), tv) 215 } 216 217 const ImplementsGetwd = true 218 219 //sys Getcwd(buf []byte) (n int, err error) 220 221 func Getwd() (wd string, err error) { 222 var buf [PathMax]byte 223 n, err := Getcwd(buf[0:]) 224 if err != nil { 225 return "", err 226 } 227 // Getcwd returns the number of bytes written to buf, including the NUL. 228 if n < 1 || n > len(buf) || buf[n-1] != 0 { 229 return "", EINVAL 230 } 231 return string(buf[0 : n-1]), nil 232 } 233 234 func Getgroups() (gids []int, err error) { 235 n, err := getgroups(0, nil) 236 if err != nil { 237 return nil, err 238 } 239 if n == 0 { 240 return nil, nil 241 } 242 243 // Sanity check group count. Max is 1<<16 on Linux. 244 if n < 0 || n > 1<<20 { 245 return nil, EINVAL 246 } 247 248 a := make([]_Gid_t, n) 249 n, err = getgroups(n, &a[0]) 250 if err != nil { 251 return nil, err 252 } 253 gids = make([]int, n) 254 for i, v := range a[0:n] { 255 gids[i] = int(v) 256 } 257 return 258 } 259 260 func Setgroups(gids []int) (err error) { 261 if len(gids) == 0 { 262 return setgroups(0, nil) 263 } 264 265 a := make([]_Gid_t, len(gids)) 266 for i, v := range gids { 267 a[i] = _Gid_t(v) 268 } 269 return setgroups(len(a), &a[0]) 270 } 271 272 type WaitStatus uint32 273 274 // Wait status is 7 bits at bottom, either 0 (exited), 275 // 0x7F (stopped), or a signal number that caused an exit. 276 // The 0x80 bit is whether there was a core dump. 277 // An extra number (exit code, signal causing a stop) 278 // is in the high bits. At least that's the idea. 279 // There are various irregularities. For example, the 280 // "continued" status is 0xFFFF, distinguishing itself 281 // from stopped via the core dump bit. 282 283 const ( 284 mask = 0x7F 285 core = 0x80 286 exited = 0x00 287 stopped = 0x7F 288 shift = 8 289 ) 290 291 func (w WaitStatus) Exited() bool { return w&mask == exited } 292 293 func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != exited } 294 295 func (w WaitStatus) Stopped() bool { return w&0xFF == stopped } 296 297 func (w WaitStatus) Continued() bool { return w == 0xFFFF } 298 299 func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 } 300 301 func (w WaitStatus) ExitStatus() int { 302 if !w.Exited() { 303 return -1 304 } 305 return int(w>>shift) & 0xFF 306 } 307 308 func (w WaitStatus) Signal() Signal { 309 if !w.Signaled() { 310 return -1 311 } 312 return Signal(w & mask) 313 } 314 315 func (w WaitStatus) StopSignal() Signal { 316 if !w.Stopped() { 317 return -1 318 } 319 return Signal(w>>shift) & 0xFF 320 } 321 322 func (w WaitStatus) TrapCause() int { 323 if w.StopSignal() != SIGTRAP { 324 return -1 325 } 326 return int(w>>shift) >> 8 327 } 328 329 //sys wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error) 330 331 func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) { 332 var status _C_int 333 wpid, err = wait4(pid, &status, options, rusage) 334 if wstatus != nil { 335 *wstatus = WaitStatus(status) 336 } 337 return 338 } 339 340 func Mkfifo(path string, mode uint32) (err error) { 341 return Mknod(path, mode|S_IFIFO, 0) 342 } 343 344 func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) { 345 if sa.Port < 0 || sa.Port > 0xFFFF { 346 return nil, 0, EINVAL 347 } 348 sa.raw.Family = AF_INET 349 p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port)) 350 p[0] = byte(sa.Port >> 8) 351 p[1] = byte(sa.Port) 352 for i := 0; i < len(sa.Addr); i++ { 353 sa.raw.Addr[i] = sa.Addr[i] 354 } 355 return unsafe.Pointer(&sa.raw), SizeofSockaddrInet4, nil 356 } 357 358 func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) { 359 if sa.Port < 0 || sa.Port > 0xFFFF { 360 return nil, 0, EINVAL 361 } 362 sa.raw.Family = AF_INET6 363 p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port)) 364 p[0] = byte(sa.Port >> 8) 365 p[1] = byte(sa.Port) 366 sa.raw.Scope_id = sa.ZoneId 367 for i := 0; i < len(sa.Addr); i++ { 368 sa.raw.Addr[i] = sa.Addr[i] 369 } 370 return unsafe.Pointer(&sa.raw), SizeofSockaddrInet6, nil 371 } 372 373 func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) { 374 name := sa.Name 375 n := len(name) 376 if n > len(sa.raw.Path) { 377 return nil, 0, EINVAL 378 } 379 if n == len(sa.raw.Path) && name[0] != '@' { 380 return nil, 0, EINVAL 381 } 382 sa.raw.Family = AF_UNIX 383 for i := 0; i < n; i++ { 384 sa.raw.Path[i] = int8(name[i]) 385 } 386 // length is family (uint16), name, NUL. 387 sl := _Socklen(2) 388 if n > 0 { 389 sl += _Socklen(n) + 1 390 } 391 if sa.raw.Path[0] == '@' { 392 sa.raw.Path[0] = 0 393 // Don't count trailing NUL for abstract address. 394 sl-- 395 } 396 397 return unsafe.Pointer(&sa.raw), sl, nil 398 } 399 400 type SockaddrLinklayer struct { 401 Protocol uint16 402 Ifindex int 403 Hatype uint16 404 Pkttype uint8 405 Halen uint8 406 Addr [8]byte 407 raw RawSockaddrLinklayer 408 } 409 410 func (sa *SockaddrLinklayer) sockaddr() (unsafe.Pointer, _Socklen, error) { 411 if sa.Ifindex < 0 || sa.Ifindex > 0x7fffffff { 412 return nil, 0, EINVAL 413 } 414 sa.raw.Family = AF_PACKET 415 sa.raw.Protocol = sa.Protocol 416 sa.raw.Ifindex = int32(sa.Ifindex) 417 sa.raw.Hatype = sa.Hatype 418 sa.raw.Pkttype = sa.Pkttype 419 sa.raw.Halen = sa.Halen 420 for i := 0; i < len(sa.Addr); i++ { 421 sa.raw.Addr[i] = sa.Addr[i] 422 } 423 return unsafe.Pointer(&sa.raw), SizeofSockaddrLinklayer, nil 424 } 425 426 type SockaddrNetlink struct { 427 Family uint16 428 Pad uint16 429 Pid uint32 430 Groups uint32 431 raw RawSockaddrNetlink 432 } 433 434 func (sa *SockaddrNetlink) sockaddr() (unsafe.Pointer, _Socklen, error) { 435 sa.raw.Family = AF_NETLINK 436 sa.raw.Pad = sa.Pad 437 sa.raw.Pid = sa.Pid 438 sa.raw.Groups = sa.Groups 439 return unsafe.Pointer(&sa.raw), SizeofSockaddrNetlink, nil 440 } 441 442 func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, error) { 443 switch rsa.Addr.Family { 444 case AF_NETLINK: 445 pp := (*RawSockaddrNetlink)(unsafe.Pointer(rsa)) 446 sa := new(SockaddrNetlink) 447 sa.Family = pp.Family 448 sa.Pad = pp.Pad 449 sa.Pid = pp.Pid 450 sa.Groups = pp.Groups 451 return sa, nil 452 453 case AF_PACKET: 454 pp := (*RawSockaddrLinklayer)(unsafe.Pointer(rsa)) 455 sa := new(SockaddrLinklayer) 456 sa.Protocol = pp.Protocol 457 sa.Ifindex = int(pp.Ifindex) 458 sa.Hatype = pp.Hatype 459 sa.Pkttype = pp.Pkttype 460 sa.Halen = pp.Halen 461 for i := 0; i < len(sa.Addr); i++ { 462 sa.Addr[i] = pp.Addr[i] 463 } 464 return sa, nil 465 466 case AF_UNIX: 467 pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa)) 468 sa := new(SockaddrUnix) 469 if pp.Path[0] == 0 { 470 // "Abstract" Unix domain socket. 471 // Rewrite leading NUL as @ for textual display. 472 // (This is the standard convention.) 473 // Not friendly to overwrite in place, 474 // but the callers below don't care. 475 pp.Path[0] = '@' 476 } 477 478 // Assume path ends at NUL. 479 // This is not technically the Linux semantics for 480 // abstract Unix domain sockets--they are supposed 481 // to be uninterpreted fixed-size binary blobs--but 482 // everyone uses this convention. 483 n := 0 484 for n < len(pp.Path) && pp.Path[n] != 0 { 485 n++ 486 } 487 bytes := (*[len(pp.Path)]byte)(unsafe.Pointer(&pp.Path[0]))[0:n] 488 sa.Name = string(bytes) 489 return sa, nil 490 491 case AF_INET: 492 pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa)) 493 sa := new(SockaddrInet4) 494 p := (*[2]byte)(unsafe.Pointer(&pp.Port)) 495 sa.Port = int(p[0])<<8 + int(p[1]) 496 for i := 0; i < len(sa.Addr); i++ { 497 sa.Addr[i] = pp.Addr[i] 498 } 499 return sa, nil 500 501 case AF_INET6: 502 pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa)) 503 sa := new(SockaddrInet6) 504 p := (*[2]byte)(unsafe.Pointer(&pp.Port)) 505 sa.Port = int(p[0])<<8 + int(p[1]) 506 sa.ZoneId = pp.Scope_id 507 for i := 0; i < len(sa.Addr); i++ { 508 sa.Addr[i] = pp.Addr[i] 509 } 510 return sa, nil 511 } 512 return nil, EAFNOSUPPORT 513 } 514 515 func Accept(fd int) (nfd int, sa Sockaddr, err error) { 516 var rsa RawSockaddrAny 517 var len _Socklen = SizeofSockaddrAny 518 nfd, err = accept(fd, &rsa, &len) 519 if err != nil { 520 return 521 } 522 sa, err = anyToSockaddr(&rsa) 523 if err != nil { 524 Close(nfd) 525 nfd = 0 526 } 527 return 528 } 529 530 func Accept4(fd int, flags int) (nfd int, sa Sockaddr, err error) { 531 var rsa RawSockaddrAny 532 var len _Socklen = SizeofSockaddrAny 533 nfd, err = accept4(fd, &rsa, &len, flags) 534 if err != nil { 535 return 536 } 537 if len > SizeofSockaddrAny { 538 panic("RawSockaddrAny too small") 539 } 540 sa, err = anyToSockaddr(&rsa) 541 if err != nil { 542 Close(nfd) 543 nfd = 0 544 } 545 return 546 } 547 548 func Getsockname(fd int) (sa Sockaddr, err error) { 549 var rsa RawSockaddrAny 550 var len _Socklen = SizeofSockaddrAny 551 if err = getsockname(fd, &rsa, &len); err != nil { 552 return 553 } 554 return anyToSockaddr(&rsa) 555 } 556 557 func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) { 558 vallen := _Socklen(4) 559 err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen) 560 return value, err 561 } 562 563 func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) { 564 var value IPMreq 565 vallen := _Socklen(SizeofIPMreq) 566 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 567 return &value, err 568 } 569 570 func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) { 571 var value IPMreqn 572 vallen := _Socklen(SizeofIPMreqn) 573 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 574 return &value, err 575 } 576 577 func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) { 578 var value IPv6Mreq 579 vallen := _Socklen(SizeofIPv6Mreq) 580 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 581 return &value, err 582 } 583 584 func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) { 585 var value IPv6MTUInfo 586 vallen := _Socklen(SizeofIPv6MTUInfo) 587 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 588 return &value, err 589 } 590 591 func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) { 592 var value ICMPv6Filter 593 vallen := _Socklen(SizeofICMPv6Filter) 594 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 595 return &value, err 596 } 597 598 func GetsockoptUcred(fd, level, opt int) (*Ucred, error) { 599 var value Ucred 600 vallen := _Socklen(SizeofUcred) 601 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 602 return &value, err 603 } 604 605 func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) { 606 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq)) 607 } 608 609 func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) { 610 var msg Msghdr 611 var rsa RawSockaddrAny 612 msg.Name = (*byte)(unsafe.Pointer(&rsa)) 613 msg.Namelen = uint32(SizeofSockaddrAny) 614 var iov Iovec 615 if len(p) > 0 { 616 iov.Base = &p[0] 617 iov.SetLen(len(p)) 618 } 619 var dummy byte 620 if len(oob) > 0 { 621 if len(p) == 0 { 622 var sockType int 623 sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE) 624 if err != nil { 625 return 626 } 627 // receive at least one normal byte 628 if sockType != SOCK_DGRAM { 629 iov.Base = &dummy 630 iov.SetLen(1) 631 } 632 } 633 msg.Control = &oob[0] 634 msg.SetControllen(len(oob)) 635 } 636 msg.Iov = &iov 637 msg.Iovlen = 1 638 if n, err = recvmsg(fd, &msg, flags); err != nil { 639 return 640 } 641 oobn = int(msg.Controllen) 642 recvflags = int(msg.Flags) 643 // source address is only specified if the socket is unconnected 644 if rsa.Addr.Family != AF_UNSPEC { 645 from, err = anyToSockaddr(&rsa) 646 } 647 return 648 } 649 650 func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) { 651 _, err = SendmsgN(fd, p, oob, to, flags) 652 return 653 } 654 655 func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) { 656 var ptr unsafe.Pointer 657 var salen _Socklen 658 if to != nil { 659 var err error 660 ptr, salen, err = to.sockaddr() 661 if err != nil { 662 return 0, err 663 } 664 } 665 var msg Msghdr 666 msg.Name = (*byte)(ptr) 667 msg.Namelen = uint32(salen) 668 var iov Iovec 669 if len(p) > 0 { 670 iov.Base = &p[0] 671 iov.SetLen(len(p)) 672 } 673 var dummy byte 674 if len(oob) > 0 { 675 if len(p) == 0 { 676 var sockType int 677 sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE) 678 if err != nil { 679 return 0, err 680 } 681 // send at least one normal byte 682 if sockType != SOCK_DGRAM { 683 iov.Base = &dummy 684 iov.SetLen(1) 685 } 686 } 687 msg.Control = &oob[0] 688 msg.SetControllen(len(oob)) 689 } 690 msg.Iov = &iov 691 msg.Iovlen = 1 692 if n, err = sendmsg(fd, &msg, flags); err != nil { 693 return 0, err 694 } 695 if len(oob) > 0 && len(p) == 0 { 696 n = 0 697 } 698 return n, nil 699 } 700 701 // BindToDevice binds the socket associated with fd to device. 702 func BindToDevice(fd int, device string) (err error) { 703 return SetsockoptString(fd, SOL_SOCKET, SO_BINDTODEVICE, device) 704 } 705 706 //sys ptrace(request int, pid int, addr uintptr, data uintptr) (err error) 707 708 func ptracePeek(req int, pid int, addr uintptr, out []byte) (count int, err error) { 709 // The peek requests are machine-size oriented, so we wrap it 710 // to retrieve arbitrary-length data. 711 712 // The ptrace syscall differs from glibc's ptrace. 713 // Peeks returns the word in *data, not as the return value. 714 715 var buf [sizeofPtr]byte 716 717 // Leading edge. PEEKTEXT/PEEKDATA don't require aligned 718 // access (PEEKUSER warns that it might), but if we don't 719 // align our reads, we might straddle an unmapped page 720 // boundary and not get the bytes leading up to the page 721 // boundary. 722 n := 0 723 if addr%sizeofPtr != 0 { 724 err = ptrace(req, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0]))) 725 if err != nil { 726 return 0, err 727 } 728 n += copy(out, buf[addr%sizeofPtr:]) 729 out = out[n:] 730 } 731 732 // Remainder. 733 for len(out) > 0 { 734 // We use an internal buffer to guarantee alignment. 735 // It's not documented if this is necessary, but we're paranoid. 736 err = ptrace(req, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0]))) 737 if err != nil { 738 return n, err 739 } 740 copied := copy(out, buf[0:]) 741 n += copied 742 out = out[copied:] 743 } 744 745 return n, nil 746 } 747 748 func PtracePeekText(pid int, addr uintptr, out []byte) (count int, err error) { 749 return ptracePeek(PTRACE_PEEKTEXT, pid, addr, out) 750 } 751 752 func PtracePeekData(pid int, addr uintptr, out []byte) (count int, err error) { 753 return ptracePeek(PTRACE_PEEKDATA, pid, addr, out) 754 } 755 756 func ptracePoke(pokeReq int, peekReq int, pid int, addr uintptr, data []byte) (count int, err error) { 757 // As for ptracePeek, we need to align our accesses to deal 758 // with the possibility of straddling an invalid page. 759 760 // Leading edge. 761 n := 0 762 if addr%sizeofPtr != 0 { 763 var buf [sizeofPtr]byte 764 err = ptrace(peekReq, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0]))) 765 if err != nil { 766 return 0, err 767 } 768 n += copy(buf[addr%sizeofPtr:], data) 769 word := *((*uintptr)(unsafe.Pointer(&buf[0]))) 770 err = ptrace(pokeReq, pid, addr-addr%sizeofPtr, word) 771 if err != nil { 772 return 0, err 773 } 774 data = data[n:] 775 } 776 777 // Interior. 778 for len(data) > sizeofPtr { 779 word := *((*uintptr)(unsafe.Pointer(&data[0]))) 780 err = ptrace(pokeReq, pid, addr+uintptr(n), word) 781 if err != nil { 782 return n, err 783 } 784 n += sizeofPtr 785 data = data[sizeofPtr:] 786 } 787 788 // Trailing edge. 789 if len(data) > 0 { 790 var buf [sizeofPtr]byte 791 err = ptrace(peekReq, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0]))) 792 if err != nil { 793 return n, err 794 } 795 copy(buf[0:], data) 796 word := *((*uintptr)(unsafe.Pointer(&buf[0]))) 797 err = ptrace(pokeReq, pid, addr+uintptr(n), word) 798 if err != nil { 799 return n, err 800 } 801 n += len(data) 802 } 803 804 return n, nil 805 } 806 807 func PtracePokeText(pid int, addr uintptr, data []byte) (count int, err error) { 808 return ptracePoke(PTRACE_POKETEXT, PTRACE_PEEKTEXT, pid, addr, data) 809 } 810 811 func PtracePokeData(pid int, addr uintptr, data []byte) (count int, err error) { 812 return ptracePoke(PTRACE_POKEDATA, PTRACE_PEEKDATA, pid, addr, data) 813 } 814 815 func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) { 816 return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout))) 817 } 818 819 func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) { 820 return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs))) 821 } 822 823 func PtraceSetOptions(pid int, options int) (err error) { 824 return ptrace(PTRACE_SETOPTIONS, pid, 0, uintptr(options)) 825 } 826 827 func PtraceGetEventMsg(pid int) (msg uint, err error) { 828 var data _C_long 829 err = ptrace(PTRACE_GETEVENTMSG, pid, 0, uintptr(unsafe.Pointer(&data))) 830 msg = uint(data) 831 return 832 } 833 834 func PtraceCont(pid int, signal int) (err error) { 835 return ptrace(PTRACE_CONT, pid, 0, uintptr(signal)) 836 } 837 838 func PtraceSyscall(pid int, signal int) (err error) { 839 return ptrace(PTRACE_SYSCALL, pid, 0, uintptr(signal)) 840 } 841 842 func PtraceSingleStep(pid int) (err error) { return ptrace(PTRACE_SINGLESTEP, pid, 0, 0) } 843 844 func PtraceAttach(pid int) (err error) { return ptrace(PTRACE_ATTACH, pid, 0, 0) } 845 846 func PtraceDetach(pid int) (err error) { return ptrace(PTRACE_DETACH, pid, 0, 0) } 847 848 //sys reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error) 849 850 func Reboot(cmd int) (err error) { 851 return reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, "") 852 } 853 854 func ReadDirent(fd int, buf []byte) (n int, err error) { 855 return Getdents(fd, buf) 856 } 857 858 func direntIno(buf []byte) (uint64, bool) { 859 return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino)) 860 } 861 862 func direntReclen(buf []byte) (uint64, bool) { 863 return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen)) 864 } 865 866 func direntNamlen(buf []byte) (uint64, bool) { 867 reclen, ok := direntReclen(buf) 868 if !ok { 869 return 0, false 870 } 871 return reclen - uint64(unsafe.Offsetof(Dirent{}.Name)), true 872 } 873 874 //sys mount(source string, target string, fstype string, flags uintptr, data *byte) (err error) 875 876 func Mount(source string, target string, fstype string, flags uintptr, data string) (err error) { 877 // Certain file systems get rather angry and EINVAL if you give 878 // them an empty string of data, rather than NULL. 879 if data == "" { 880 return mount(source, target, fstype, flags, nil) 881 } 882 datap, err := BytePtrFromString(data) 883 if err != nil { 884 return err 885 } 886 return mount(source, target, fstype, flags, datap) 887 } 888 889 // Sendto 890 // Recvfrom 891 // Socketpair 892 893 /* 894 * Direct access 895 */ 896 //sys Acct(path string) (err error) 897 //sys Adjtimex(buf *Timex) (state int, err error) 898 //sys Chdir(path string) (err error) 899 //sys Chroot(path string) (err error) 900 //sys Close(fd int) (err error) 901 //sys Dup(oldfd int) (fd int, err error) 902 //sys Dup3(oldfd int, newfd int, flags int) (err error) 903 //sysnb EpollCreate1(flag int) (fd int, err error) 904 //sysnb EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error) 905 //sys Fallocate(fd int, mode uint32, off int64, len int64) (err error) 906 //sys Fchdir(fd int) (err error) 907 //sys Fchmod(fd int, mode uint32) (err error) 908 //sys Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error) 909 //sys fcntl(fd int, cmd int, arg int) (val int, err error) 910 //sys Fdatasync(fd int) (err error) 911 //sys Flock(fd int, how int) (err error) 912 //sys Fsync(fd int) (err error) 913 //sys Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64 914 //sysnb Getpgid(pid int) (pgid int, err error) 915 916 func Getpgrp() (pid int) { 917 pid, _ = Getpgid(0) 918 return 919 } 920 921 //sysnb Getpid() (pid int) 922 //sysnb Getppid() (ppid int) 923 //sys Getpriority(which int, who int) (prio int, err error) 924 //sysnb Getrusage(who int, rusage *Rusage) (err error) 925 //sysnb Gettid() (tid int) 926 //sys Getxattr(path string, attr string, dest []byte) (sz int, err error) 927 //sys InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error) 928 //sysnb InotifyInit1(flags int) (fd int, err error) 929 //sysnb InotifyRmWatch(fd int, watchdesc uint32) (success int, err error) 930 //sysnb Kill(pid int, sig Signal) (err error) 931 //sys Klogctl(typ int, buf []byte) (n int, err error) = SYS_SYSLOG 932 //sys Listxattr(path string, dest []byte) (sz int, err error) 933 //sys Mkdirat(dirfd int, path string, mode uint32) (err error) 934 //sys Mknodat(dirfd int, path string, mode uint32, dev int) (err error) 935 //sys Nanosleep(time *Timespec, leftover *Timespec) (err error) 936 //sys PivotRoot(newroot string, putold string) (err error) = SYS_PIVOT_ROOT 937 //sysnb prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT64 938 //sys read(fd int, p []byte) (n int, err error) 939 //sys Removexattr(path string, attr string) (err error) 940 //sys Setdomainname(p []byte) (err error) 941 //sys Sethostname(p []byte) (err error) 942 //sysnb Setpgid(pid int, pgid int) (err error) 943 //sysnb Setsid() (pid int, err error) 944 //sysnb Settimeofday(tv *Timeval) (err error) 945 946 // issue 1435. 947 // On linux Setuid and Setgid only affects the current thread, not the process. 948 // This does not match what most callers expect so we must return an error 949 // here rather than letting the caller think that the call succeeded. 950 951 func Setuid(uid int) (err error) { 952 return EOPNOTSUPP 953 } 954 955 func Setgid(gid int) (err error) { 956 return EOPNOTSUPP 957 } 958 959 //sys Setpriority(which int, who int, prio int) (err error) 960 //sys Setxattr(path string, attr string, data []byte, flags int) (err error) 961 //sys Sync() 962 //sysnb Sysinfo(info *Sysinfo_t) (err error) 963 //sys Tee(rfd int, wfd int, len int, flags int) (n int64, err error) 964 //sysnb Tgkill(tgid int, tid int, sig Signal) (err error) 965 //sysnb Times(tms *Tms) (ticks uintptr, err error) 966 //sysnb Umask(mask int) (oldmask int) 967 //sysnb Uname(buf *Utsname) (err error) 968 //sys Unmount(target string, flags int) (err error) = SYS_UMOUNT2 969 //sys Unshare(flags int) (err error) 970 //sys write(fd int, p []byte) (n int, err error) 971 //sys exitThread(code int) (err error) = SYS_EXIT 972 //sys readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ 973 //sys writelen(fd int, p *byte, np int) (n int, err error) = SYS_WRITE 974 975 // mmap varies by architecture; see syscall_linux_*.go. 976 //sys munmap(addr uintptr, length uintptr) (err error) 977 978 var mapper = &mmapper{ 979 active: make(map[*byte][]byte), 980 mmap: mmap, 981 munmap: munmap, 982 } 983 984 func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) { 985 return mapper.Mmap(fd, offset, length, prot, flags) 986 } 987 988 func Munmap(b []byte) (err error) { 989 return mapper.Munmap(b) 990 } 991 992 //sys Madvise(b []byte, advice int) (err error) 993 //sys Mprotect(b []byte, prot int) (err error) 994 //sys Mlock(b []byte) (err error) 995 //sys Munlock(b []byte) (err error) 996 //sys Mlockall(flags int) (err error) 997 //sys Munlockall() (err error)