diff options
Diffstat (limited to 'runsc/sandbox')
-rw-r--r-- | runsc/sandbox/BUILD | 5 | ||||
-rw-r--r-- | runsc/sandbox/network.go | 10 | ||||
-rw-r--r-- | runsc/sandbox/sandbox.go | 232 |
3 files changed, 159 insertions, 88 deletions
diff --git a/runsc/sandbox/BUILD b/runsc/sandbox/BUILD index c0de9a28f..7fdceaab6 100644 --- a/runsc/sandbox/BUILD +++ b/runsc/sandbox/BUILD @@ -9,7 +9,7 @@ go_library( "network_unsafe.go", "sandbox.go", ], - importpath = "gvisor.googlesource.com/gvisor/runsc/sandbox", + importpath = "gvisor.dev/gvisor/runsc/sandbox", visibility = [ "//runsc:__subpackages__", ], @@ -18,9 +18,10 @@ go_library( "//pkg/control/server", "//pkg/log", "//pkg/sentry/control", - "//pkg/sentry/platform/kvm", + "//pkg/sentry/platform", "//pkg/urpc", "//runsc/boot", + "//runsc/boot/platforms", "//runsc/cgroup", "//runsc/console", "//runsc/specutils", diff --git a/runsc/sandbox/network.go b/runsc/sandbox/network.go index 1fd091514..a965a9dcb 100644 --- a/runsc/sandbox/network.go +++ b/runsc/sandbox/network.go @@ -27,10 +27,10 @@ import ( specs "github.com/opencontainers/runtime-spec/specs-go" "github.com/vishvananda/netlink" "golang.org/x/sys/unix" - "gvisor.googlesource.com/gvisor/pkg/log" - "gvisor.googlesource.com/gvisor/pkg/urpc" - "gvisor.googlesource.com/gvisor/runsc/boot" - "gvisor.googlesource.com/gvisor/runsc/specutils" + "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/urpc" + "gvisor.dev/gvisor/runsc/boot" + "gvisor.dev/gvisor/runsc/specutils" ) const ( @@ -228,7 +228,7 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, enableGSO if err != nil { return fmt.Errorf("getting link for interface %q: %v", iface.Name, err) } - link.LinkAddress = []byte(ifaceLink.Attrs().HardwareAddr) + link.LinkAddress = ifaceLink.Attrs().HardwareAddr log.Debugf("Setting up network channels") // Create the socket for the device. diff --git a/runsc/sandbox/sandbox.go b/runsc/sandbox/sandbox.go index 032190636..4a11f617d 100644 --- a/runsc/sandbox/sandbox.go +++ b/runsc/sandbox/sandbox.go @@ -28,16 +28,17 @@ import ( "github.com/cenkalti/backoff" specs "github.com/opencontainers/runtime-spec/specs-go" "github.com/syndtr/gocapability/capability" - "gvisor.googlesource.com/gvisor/pkg/control/client" - "gvisor.googlesource.com/gvisor/pkg/control/server" - "gvisor.googlesource.com/gvisor/pkg/log" - "gvisor.googlesource.com/gvisor/pkg/sentry/control" - "gvisor.googlesource.com/gvisor/pkg/sentry/platform/kvm" - "gvisor.googlesource.com/gvisor/pkg/urpc" - "gvisor.googlesource.com/gvisor/runsc/boot" - "gvisor.googlesource.com/gvisor/runsc/cgroup" - "gvisor.googlesource.com/gvisor/runsc/console" - "gvisor.googlesource.com/gvisor/runsc/specutils" + "gvisor.dev/gvisor/pkg/control/client" + "gvisor.dev/gvisor/pkg/control/server" + "gvisor.dev/gvisor/pkg/log" + "gvisor.dev/gvisor/pkg/sentry/control" + "gvisor.dev/gvisor/pkg/sentry/platform" + "gvisor.dev/gvisor/pkg/urpc" + "gvisor.dev/gvisor/runsc/boot" + "gvisor.dev/gvisor/runsc/boot/platforms" + "gvisor.dev/gvisor/runsc/cgroup" + "gvisor.dev/gvisor/runsc/console" + "gvisor.dev/gvisor/runsc/specutils" ) // Sandbox wraps a sandbox process. @@ -73,10 +74,46 @@ type Sandbox struct { statusMu sync.Mutex } +// Args is used to configure a new sandbox. +type Args struct { + // ID is the sandbox unique identifier. + ID string + + // Spec is the OCI spec that describes the container. + Spec *specs.Spec + + // BundleDir is the directory containing the container bundle. + BundleDir string + + // ConsoleSocket is the path to a unix domain socket that will receive + // the console FD. It may be empty. + ConsoleSocket string + + // UserLog is the filename to send user-visible logs to. It may be empty. + UserLog string + + // IOFiles is the list of files that connect to a 9P endpoint for the mounts + // points using Gofers. They must be in the same order as mounts appear in + // the spec. + IOFiles []*os.File + + // MountsFile is a file container mount information from the spec. It's + // equivalent to the mounts from the spec, except that all paths have been + // resolved to their final absolute location. + MountsFile *os.File + + // Gcgroup is the cgroup that the sandbox is part of. + Cgroup *cgroup.Cgroup + + // Attached indicates that the sandbox lifecycle is attached with the caller. + // If the caller exits, the sandbox should exit too. + Attached bool +} + // New creates the sandbox process. The caller must call Destroy() on the // sandbox. -func New(id string, spec *specs.Spec, conf *boot.Config, bundleDir, consoleSocket, userLog string, ioFiles []*os.File, specFile *os.File, cg *cgroup.Cgroup) (*Sandbox, error) { - s := &Sandbox{ID: id, Cgroup: cg} +func New(conf *boot.Config, args *Args) (*Sandbox, error) { + s := &Sandbox{ID: args.ID, Cgroup: args.Cgroup} // The Cleanup object cleans up partially created sandboxes when an error // occurs. Any errors occurring during cleanup itself are ignored. c := specutils.MakeCleanup(func() { @@ -93,7 +130,7 @@ func New(id string, spec *specs.Spec, conf *boot.Config, bundleDir, consoleSocke defer clientSyncFile.Close() // Create the sandbox process. - err = s.createSandboxProcess(spec, conf, bundleDir, consoleSocket, userLog, ioFiles, specFile, sandboxSyncFile) + err = s.createSandboxProcess(conf, args, sandboxSyncFile) // sandboxSyncFile has to be closed to be able to detect when the sandbox // process exits unexpectedly. sandboxSyncFile.Close() @@ -291,7 +328,7 @@ func (s *Sandbox) connError(err error) error { // createSandboxProcess starts the sandbox as a subprocess by running the "boot" // command, passing in the bundle dir. -func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bundleDir, consoleSocket, userLog string, ioFiles []*os.File, mountsFile, startSyncFile *os.File) error { +func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncFile *os.File) error { // nextFD is used to get unused FDs that we can pass to the sandbox. It // starts at 3 because 0, 1, and 2 are taken by stdin/out/err. nextFD := 3 @@ -327,7 +364,7 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund // Add the "boot" command to the args. // // All flags after this must be for the boot command - cmd.Args = append(cmd.Args, "boot", "--bundle="+bundleDir) + cmd.Args = append(cmd.Args, "boot", "--bundle="+args.BundleDir) // Create a socket for the control server and donate it to the sandbox. addr := boot.ControlSocketAddr(s.ID) @@ -342,12 +379,12 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund cmd.Args = append(cmd.Args, "--controller-fd="+strconv.Itoa(nextFD)) nextFD++ - defer mountsFile.Close() - cmd.ExtraFiles = append(cmd.ExtraFiles, mountsFile) + defer args.MountsFile.Close() + cmd.ExtraFiles = append(cmd.ExtraFiles, args.MountsFile) cmd.Args = append(cmd.Args, "--mounts-fd="+strconv.Itoa(nextFD)) nextFD++ - specFile, err := specutils.OpenSpec(bundleDir) + specFile, err := specutils.OpenSpec(args.BundleDir) if err != nil { return err } @@ -361,7 +398,7 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund nextFD++ // If there is a gofer, sends all socket ends to the sandbox. - for _, f := range ioFiles { + for _, f := range args.IOFiles { defer f.Close() cmd.ExtraFiles = append(cmd.ExtraFiles, f) cmd.Args = append(cmd.Args, "--io-fds="+strconv.Itoa(nextFD)) @@ -389,23 +426,22 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund // If the console control socket file is provided, then create a new // pty master/slave pair and set the TTY on the sandbox process. - if consoleSocket != "" { + if args.ConsoleSocket != "" { cmd.Args = append(cmd.Args, "--console=true") // console.NewWithSocket will send the master on the given // socket, and return the slave. - tty, err := console.NewWithSocket(consoleSocket) + tty, err := console.NewWithSocket(args.ConsoleSocket) if err != nil { - return fmt.Errorf("setting up console with socket %q: %v", consoleSocket, err) + return fmt.Errorf("setting up console with socket %q: %v", args.ConsoleSocket, err) } defer tty.Close() // Set the TTY as a controlling TTY on the sandbox process. - // Note that the Ctty field must be the FD of the TTY in the - // *new* process, not this process. Since we are about to - // assign the TTY to nextFD, we can use that value here. - // stdin, we can use FD 0 here. cmd.SysProcAttr.Setctty = true + // The Ctty FD must be the FD in the child process's FD table, + // which will be nextFD in this case. + // See https://github.com/golang/go/issues/29458. cmd.SysProcAttr.Ctty = nextFD // Pass the tty as all stdio fds to sandbox. @@ -456,7 +492,7 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund {Type: specs.UTSNamespace}, } - if conf.Platform == boot.PlatformPtrace { + if conf.Platform == platforms.Ptrace { // TODO(b/75837838): Also set a new PID namespace so that we limit // access to other host processes. log.Infof("Sandbox will be started in the current PID namespace") @@ -469,7 +505,7 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund // Joins the network namespace if network is enabled. the sandbox talks // directly to the host network, which may have been configured in the // namespace. - if ns, ok := specutils.GetNS(specs.NetworkNamespace, spec); ok && conf.Network != boot.NetworkNone { + if ns, ok := specutils.GetNS(specs.NetworkNamespace, args.Spec); ok && conf.Network != boot.NetworkNone { log.Infof("Sandbox will be started in the container's network namespace: %+v", ns) nss = append(nss, ns) } else if conf.Network == boot.NetworkHost { @@ -483,10 +519,10 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund // inside the user namespace specified in the spec or the current namespace // if none is configured. if conf.Network == boot.NetworkHost { - if userns, ok := specutils.GetNS(specs.UserNamespace, spec); ok { + if userns, ok := specutils.GetNS(specs.UserNamespace, args.Spec); ok { log.Infof("Sandbox will be started in container's user namespace: %+v", userns) nss = append(nss, userns) - specutils.SetUIDGIDMappings(cmd, spec) + specutils.SetUIDGIDMappings(cmd, args.Spec) } else { log.Infof("Sandbox will be started in the current user namespace") } @@ -515,46 +551,64 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund } else if specutils.HasCapabilities(capability.CAP_SETUID, capability.CAP_SETGID) { log.Infof("Sandbox will be started in new user namespace") nss = append(nss, specs.LinuxNamespace{Type: specs.UserNamespace}) + cmd.Args = append(cmd.Args, "--setup-root") - // Map nobody in the new namespace to nobody in the parent namespace. - // - // A sandbox process will construct an empty - // root for itself, so it has to have the CAP_SYS_ADMIN - // capability. - // - // FIXME(b/122554829): The current implementations of - // os/exec doesn't allow to set ambient capabilities if - // a process is started in a new user namespace. As a - // workaround, we start the sandbox process with the 0 - // UID and then it constructs a chroot and sets UID to - // nobody. https://github.com/golang/go/issues/2315 - const nobody = 65534 - cmd.SysProcAttr.UidMappings = []syscall.SysProcIDMap{ - { - ContainerID: int(0), - HostID: int(nobody - 1), - Size: int(1), - }, - { - ContainerID: int(nobody), - HostID: int(nobody), - Size: int(1), - }, - } - cmd.SysProcAttr.GidMappings = []syscall.SysProcIDMap{ - { - ContainerID: int(nobody), - HostID: int(nobody), - Size: int(1), - }, + if conf.Rootless { + log.Infof("Rootless mode: sandbox will run as root inside user namespace, mapped to the current user, uid: %d, gid: %d", os.Getuid(), os.Getgid()) + cmd.SysProcAttr.UidMappings = []syscall.SysProcIDMap{ + { + ContainerID: 0, + HostID: os.Getuid(), + Size: 1, + }, + } + cmd.SysProcAttr.GidMappings = []syscall.SysProcIDMap{ + { + ContainerID: 0, + HostID: os.Getgid(), + Size: 1, + }, + } + cmd.SysProcAttr.Credential = &syscall.Credential{Uid: 0, Gid: 0} + + } else { + // Map nobody in the new namespace to nobody in the parent namespace. + // + // A sandbox process will construct an empty + // root for itself, so it has to have the CAP_SYS_ADMIN + // capability. + // + // FIXME(b/122554829): The current implementations of + // os/exec doesn't allow to set ambient capabilities if + // a process is started in a new user namespace. As a + // workaround, we start the sandbox process with the 0 + // UID and then it constructs a chroot and sets UID to + // nobody. https://github.com/golang/go/issues/2315 + const nobody = 65534 + cmd.SysProcAttr.UidMappings = []syscall.SysProcIDMap{ + { + ContainerID: 0, + HostID: nobody - 1, + Size: 1, + }, + { + ContainerID: nobody, + HostID: nobody, + Size: 1, + }, + } + cmd.SysProcAttr.GidMappings = []syscall.SysProcIDMap{ + { + ContainerID: nobody, + HostID: nobody, + Size: 1, + }, + } + + // Set credentials to run as user and group nobody. + cmd.SysProcAttr.Credential = &syscall.Credential{Uid: 0, Gid: nobody} } - // Set credentials to run as user and group nobody. - cmd.SysProcAttr.Credential = &syscall.Credential{ - Uid: 0, - Gid: nobody, - } - cmd.Args = append(cmd.Args, "--setup-root") } else { return fmt.Errorf("can't run sandbox process as user nobody since we don't have CAP_SETUID or CAP_SETGID") } @@ -580,8 +634,8 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund } } - if userLog != "" { - f, err := os.OpenFile(userLog, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0664) + if args.UserLog != "" { + f, err := os.OpenFile(args.UserLog, os.O_WRONLY|os.O_CREATE|os.O_APPEND, 0664) if err != nil { return fmt.Errorf("opening compat log file: %v", err) } @@ -600,6 +654,11 @@ func (s *Sandbox) createSandboxProcess(spec *specs.Spec, conf *boot.Config, bund log.Debugf("Donating FD %d: %q", i+3, f.Name()) } + if args.Attached { + // Kill sandbox if parent process exits in attached mode. + cmd.SysProcAttr.Pdeathsig = syscall.SIGKILL + } + log.Debugf("Starting sandbox: %s %v", binPath, cmd.Args) log.Debugf("SysProcAttr: %+v", cmd.SysProcAttr) if err := specutils.StartInNS(cmd, nss); err != nil { @@ -902,7 +961,7 @@ func (s *Sandbox) StartTrace(f *os.File) error { return nil } -// StopTrace stops a previously started trace.. +// StopTrace stops a previously started trace. func (s *Sandbox) StopTrace() error { log.Debugf("Trace stop %q", s.ID) conn, err := s.sandboxConnect() @@ -917,6 +976,21 @@ func (s *Sandbox) StopTrace() error { return nil } +// ChangeLogging changes logging options. +func (s *Sandbox) ChangeLogging(args control.LoggingArgs) error { + log.Debugf("Change logging start %q", s.ID) + conn, err := s.sandboxConnect() + if err != nil { + return err + } + defer conn.Close() + + if err := conn.Call(boot.ChangeLogging, &args, nil); err != nil { + return fmt.Errorf("changing sandbox %q logging: %v", s.ID, err) + } + return nil +} + // DestroyContainer destroys the given container. If it is the root container, // then the entire sandbox is destroyed. func (s *Sandbox) DestroyContainer(cid string) error { @@ -973,19 +1047,15 @@ func (s *Sandbox) waitForStopped() error { // deviceFileForPlatform opens the device file for the given platform. If the // platform does not need a device file, then nil is returned. -func deviceFileForPlatform(p boot.PlatformType) (*os.File, error) { - var ( - f *os.File - err error - ) - switch p { - case boot.PlatformKVM: - f, err = kvm.OpenDevice() - default: - return nil, nil +func deviceFileForPlatform(name string) (*os.File, error) { + p, err := platform.Lookup(name) + if err != nil { + return nil, err } + + f, err := p.OpenDevice() if err != nil { return nil, fmt.Errorf("opening device file for platform %q: %v", p, err) } - return f, err + return f, nil } |