diff options
Diffstat (limited to 'vendor/github.com/opencontainers/runc/libcontainer/system')
9 files changed, 395 insertions, 0 deletions
diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/linux.go b/vendor/github.com/opencontainers/runc/libcontainer/system/linux.go new file mode 100644 index 000000000..4837085a7 --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/linux.go @@ -0,0 +1,136 @@ +// +build linux + +package system + +import ( + "bufio" + "fmt" + "os" + "os/exec" + "syscall" // only for exec + "unsafe" + + "golang.org/x/sys/unix" +) + +// If arg2 is nonzero, set the "child subreaper" attribute of the +// calling process; if arg2 is zero, unset the attribute. When a +// process is marked as a child subreaper, all of the children +// that it creates, and their descendants, will be marked as +// having a subreaper. In effect, a subreaper fulfills the role +// of init(1) for its descendant processes. Upon termination of +// a process that is orphaned (i.e., its immediate parent has +// already terminated) and marked as having a subreaper, the +// nearest still living ancestor subreaper will receive a SIGCHLD +// signal and be able to wait(2) on the process to discover its +// termination status. +const PR_SET_CHILD_SUBREAPER = 36 + +type ParentDeathSignal int + +func (p ParentDeathSignal) Restore() error { + if p == 0 { + return nil + } + current, err := GetParentDeathSignal() + if err != nil { + return err + } + if p == current { + return nil + } + return p.Set() +} + +func (p ParentDeathSignal) Set() error { + return SetParentDeathSignal(uintptr(p)) +} + +func Execv(cmd string, args []string, env []string) error { + name, err := exec.LookPath(cmd) + if err != nil { + return err + } + + return syscall.Exec(name, args, env) +} + +func Prlimit(pid, resource int, limit unix.Rlimit) error { + _, _, err := unix.RawSyscall6(unix.SYS_PRLIMIT64, uintptr(pid), uintptr(resource), uintptr(unsafe.Pointer(&limit)), uintptr(unsafe.Pointer(&limit)), 0, 0) + if err != 0 { + return err + } + return nil +} + +func SetParentDeathSignal(sig uintptr) error { + if err := unix.Prctl(unix.PR_SET_PDEATHSIG, sig, 0, 0, 0); err != nil { + return err + } + return nil +} + +func GetParentDeathSignal() (ParentDeathSignal, error) { + var sig int + if err := unix.Prctl(unix.PR_GET_PDEATHSIG, uintptr(unsafe.Pointer(&sig)), 0, 0, 0); err != nil { + return -1, err + } + return ParentDeathSignal(sig), nil +} + +func SetKeepCaps() error { + if err := unix.Prctl(unix.PR_SET_KEEPCAPS, 1, 0, 0, 0); err != nil { + return err + } + + return nil +} + +func ClearKeepCaps() error { + if err := unix.Prctl(unix.PR_SET_KEEPCAPS, 0, 0, 0, 0); err != nil { + return err + } + + return nil +} + +func Setctty() error { + if err := unix.IoctlSetInt(0, unix.TIOCSCTTY, 0); err != nil { + return err + } + return nil +} + +// RunningInUserNS detects whether we are currently running in a user namespace. +// Copied from github.com/lxc/lxd/shared/util.go +func RunningInUserNS() bool { + file, err := os.Open("/proc/self/uid_map") + if err != nil { + // This kernel-provided file only exists if user namespaces are supported + return false + } + defer file.Close() + + buf := bufio.NewReader(file) + l, _, err := buf.ReadLine() + if err != nil { + return false + } + + line := string(l) + var a, b, c int64 + fmt.Sscanf(line, "%d %d %d", &a, &b, &c) + /* + * We assume we are in the initial user namespace if we have a full + * range - 4294967295 uids starting at uid 0. + */ + if a == 0 && b == 0 && c == 4294967295 { + return false + } + return true +} + +// SetSubreaper sets the value i as the subreaper setting for the calling process +func SetSubreaper(i int) error { + return unix.Prctl(PR_SET_CHILD_SUBREAPER, uintptr(i), 0, 0, 0) +} diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/proc.go b/vendor/github.com/opencontainers/runc/libcontainer/system/proc.go new file mode 100644 index 000000000..79232a437 --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/proc.go @@ -0,0 +1,113 @@ +package system + +import ( + "fmt" + "io/ioutil" + "path/filepath" + "strconv" + "strings" +) + +// State is the status of a process. +type State rune + +const ( // Only values for Linux 3.14 and later are listed here + Dead State = 'X' + DiskSleep State = 'D' + Running State = 'R' + Sleeping State = 'S' + Stopped State = 'T' + TracingStop State = 't' + Zombie State = 'Z' +) + +// String forms of the state from proc(5)'s documentation for +// /proc/[pid]/status' "State" field. +func (s State) String() string { + switch s { + case Dead: + return "dead" + case DiskSleep: + return "disk sleep" + case Running: + return "running" + case Sleeping: + return "sleeping" + case Stopped: + return "stopped" + case TracingStop: + return "tracing stop" + case Zombie: + return "zombie" + default: + return fmt.Sprintf("unknown (%c)", s) + } +} + +// Stat_t represents the information from /proc/[pid]/stat, as +// described in proc(5) with names based on the /proc/[pid]/status +// fields. +type Stat_t struct { + // PID is the process ID. + PID uint + + // Name is the command run by the process. + Name string + + // State is the state of the process. + State State + + // StartTime is the number of clock ticks after system boot (since + // Linux 2.6). + StartTime uint64 +} + +// Stat returns a Stat_t instance for the specified process. +func Stat(pid int) (stat Stat_t, err error) { + bytes, err := ioutil.ReadFile(filepath.Join("/proc", strconv.Itoa(pid), "stat")) + if err != nil { + return stat, err + } + return parseStat(string(bytes)) +} + +// GetProcessStartTime is deprecated. Use Stat(pid) and +// Stat_t.StartTime instead. +func GetProcessStartTime(pid int) (string, error) { + stat, err := Stat(pid) + if err != nil { + return "", err + } + return fmt.Sprintf("%d", stat.StartTime), nil +} + +func parseStat(data string) (stat Stat_t, err error) { + // From proc(5), field 2 could contain space and is inside `(` and `)`. + // The following is an example: + // 89653 (gunicorn: maste) S 89630 89653 89653 0 -1 4194560 29689 28896 0 3 146 32 76 19 20 0 1 0 2971844 52965376 3920 18446744073709551615 1 1 0 0 0 0 0 16781312 137447943 0 0 0 17 1 0 0 0 0 0 0 0 0 0 0 0 0 0 + i := strings.LastIndex(data, ")") + if i <= 2 || i >= len(data)-1 { + return stat, fmt.Errorf("invalid stat data: %q", data) + } + + parts := strings.SplitN(data[:i], "(", 2) + if len(parts) != 2 { + return stat, fmt.Errorf("invalid stat data: %q", data) + } + + stat.Name = parts[1] + _, err = fmt.Sscanf(parts[0], "%d", &stat.PID) + if err != nil { + return stat, err + } + + // parts indexes should be offset by 3 from the field number given + // proc(5), because parts is zero-indexed and we've removed fields + // one (PID) and two (Name) in the paren-split. + parts = strings.Split(data[i+2:], " ") + var state int + fmt.Sscanf(parts[3-3], "%c", &state) + stat.State = State(state) + fmt.Sscanf(parts[22-3], "%d", &stat.StartTime) + return stat, nil +} diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_386.go b/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_386.go new file mode 100644 index 000000000..3f7235ed1 --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_386.go @@ -0,0 +1,25 @@ +// +build linux,386 + +package system + +import ( + "golang.org/x/sys/unix" +) + +// Setuid sets the uid of the calling thread to the specified uid. +func Setuid(uid int) (err error) { + _, _, e1 := unix.RawSyscall(unix.SYS_SETUID32, uintptr(uid), 0, 0) + if e1 != 0 { + err = e1 + } + return +} + +// Setgid sets the gid of the calling thread to the specified gid. +func Setgid(gid int) (err error) { + _, _, e1 := unix.RawSyscall(unix.SYS_SETGID32, uintptr(gid), 0, 0) + if e1 != 0 { + err = e1 + } + return +} diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_64.go b/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_64.go new file mode 100644 index 000000000..d7891a2ff --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_64.go @@ -0,0 +1,25 @@ +// +build linux,arm64 linux,amd64 linux,ppc linux,ppc64 linux,ppc64le linux,s390x + +package system + +import ( + "golang.org/x/sys/unix" +) + +// Setuid sets the uid of the calling thread to the specified uid. +func Setuid(uid int) (err error) { + _, _, e1 := unix.RawSyscall(unix.SYS_SETUID, uintptr(uid), 0, 0) + if e1 != 0 { + err = e1 + } + return +} + +// Setgid sets the gid of the calling thread to the specified gid. +func Setgid(gid int) (err error) { + _, _, e1 := unix.RawSyscall(unix.SYS_SETGID, uintptr(gid), 0, 0) + if e1 != 0 { + err = e1 + } + return +} diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_arm.go b/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_arm.go new file mode 100644 index 000000000..31ff3deb1 --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/syscall_linux_arm.go @@ -0,0 +1,25 @@ +// +build linux,arm + +package system + +import ( + "golang.org/x/sys/unix" +) + +// Setuid sets the uid of the calling thread to the specified uid. +func Setuid(uid int) (err error) { + _, _, e1 := unix.RawSyscall(unix.SYS_SETUID32, uintptr(uid), 0, 0) + if e1 != 0 { + err = e1 + } + return +} + +// Setgid sets the gid of the calling thread to the specified gid. +func Setgid(gid int) (err error) { + _, _, e1 := unix.RawSyscall(unix.SYS_SETGID32, uintptr(gid), 0, 0) + if e1 != 0 { + err = e1 + } + return +} diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/sysconfig.go b/vendor/github.com/opencontainers/runc/libcontainer/system/sysconfig.go new file mode 100644 index 000000000..b3a07cba3 --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/sysconfig.go @@ -0,0 +1,12 @@ +// +build cgo,linux cgo,freebsd + +package system + +/* +#include <unistd.h> +*/ +import "C" + +func GetClockTicks() int { + return int(C.sysconf(C._SC_CLK_TCK)) +} diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/sysconfig_notcgo.go b/vendor/github.com/opencontainers/runc/libcontainer/system/sysconfig_notcgo.go new file mode 100644 index 000000000..d93b5d5fd --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/sysconfig_notcgo.go @@ -0,0 +1,15 @@ +// +build !cgo windows + +package system + +func GetClockTicks() int { + // TODO figure out a better alternative for platforms where we're missing cgo + // + // TODO Windows. This could be implemented using Win32 QueryPerformanceFrequency(). + // https://msdn.microsoft.com/en-us/library/windows/desktop/ms644905(v=vs.85).aspx + // + // An example of its usage can be found here. + // https://msdn.microsoft.com/en-us/library/windows/desktop/dn553408(v=vs.85).aspx + + return 100 +} diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/unsupported.go b/vendor/github.com/opencontainers/runc/libcontainer/system/unsupported.go new file mode 100644 index 000000000..e7cfd62b2 --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/unsupported.go @@ -0,0 +1,9 @@ +// +build !linux + +package system + +// RunningInUserNS is a stub for non-Linux systems +// Always returns false +func RunningInUserNS() bool { + return false +} diff --git a/vendor/github.com/opencontainers/runc/libcontainer/system/xattrs_linux.go b/vendor/github.com/opencontainers/runc/libcontainer/system/xattrs_linux.go new file mode 100644 index 000000000..a6823fc99 --- /dev/null +++ b/vendor/github.com/opencontainers/runc/libcontainer/system/xattrs_linux.go @@ -0,0 +1,35 @@ +package system + +import "golang.org/x/sys/unix" + +// Returns a []byte slice if the xattr is set and nil otherwise +// Requires path and its attribute as arguments +func Lgetxattr(path string, attr string) ([]byte, error) { + var sz int + // Start with a 128 length byte array + dest := make([]byte, 128) + sz, errno := unix.Lgetxattr(path, attr, dest) + + switch { + case errno == unix.ENODATA: + return nil, errno + case errno == unix.ENOTSUP: + return nil, errno + case errno == unix.ERANGE: + // 128 byte array might just not be good enough, + // A dummy buffer is used to get the real size + // of the xattrs on disk + sz, errno = unix.Lgetxattr(path, attr, []byte{}) + if errno != nil { + return nil, errno + } + dest = make([]byte, sz) + sz, errno = unix.Lgetxattr(path, attr, dest) + if errno != nil { + return nil, errno + } + case errno != nil: + return nil, errno + } + return dest[:sz], nil +} |