diff options
| -rw-r--r-- | runsc/cmd/do.go | 45 |
1 files changed, 29 insertions, 16 deletions
diff --git a/runsc/cmd/do.go b/runsc/cmd/do.go index d1f2e9e6d..640de4c47 100644 --- a/runsc/cmd/do.go +++ b/runsc/cmd/do.go @@ -17,6 +17,7 @@ package cmd import ( "context" "encoding/json" + "errors" "fmt" "io/ioutil" "math/rand" @@ -36,6 +37,8 @@ import ( "gvisor.dev/gvisor/runsc/specutils" ) +var errNoDefaultInterface = errors.New("no default interface found") + // Do implements subcommands.Command for the "do" command. It sets up a simple // sandbox and executes the command inside it. See Usage() for more details. type Do struct { @@ -126,26 +129,28 @@ func (c *Do) Execute(_ context.Context, f *flag.FlagSet, args ...interface{}) su cid := fmt.Sprintf("runsc-%06d", rand.Int31n(1000000)) if conf.Network == config.NetworkNone { - netns := specs.LinuxNamespace{ - Type: specs.NetworkNamespace, - } - if spec.Linux != nil { - panic("spec.Linux is not nil") - } - spec.Linux = &specs.Linux{Namespaces: []specs.LinuxNamespace{netns}} + addNamespace(spec, specs.LinuxNamespace{Type: specs.NetworkNamespace}) } else if conf.Rootless { if conf.Network == config.NetworkSandbox { - c.notifyUser("*** Warning: using host network due to --rootless ***") + c.notifyUser("*** Warning: sandbox network isn't supported with --rootless, switching to host ***") conf.Network = config.NetworkHost } } else { - clean, err := c.setupNet(cid, spec) - if err != nil { + switch clean, err := c.setupNet(cid, spec); err { + case errNoDefaultInterface: + log.Warningf("Network interface not found, using internal network") + addNamespace(spec, specs.LinuxNamespace{Type: specs.NetworkNamespace}) + conf.Network = config.NetworkHost + + case nil: + // Setup successfull. + defer clean() + + default: return Errorf("Error setting up network: %v", err) } - defer clean() } out, err := json.Marshal(spec) @@ -199,6 +204,13 @@ func (c *Do) Execute(_ context.Context, f *flag.FlagSet, args ...interface{}) su return subcommands.ExitSuccess } +func addNamespace(spec *specs.Spec, ns specs.LinuxNamespace) { + if spec.Linux == nil { + spec.Linux = &specs.Linux{} + } + spec.Linux.Namespaces = append(spec.Linux.Namespaces, ns) +} + func (c *Do) notifyUser(format string, v ...interface{}) { if !c.quiet { fmt.Printf(format+"\n", v...) @@ -219,10 +231,14 @@ func resolvePath(path string) (string, error) { return path, nil } +// setupNet setups up the sandbox network, including the creation of a network +// namespace, and iptable rules to redirect the traffic. Returns a cleanup +// function to tear down the network. Returns errNoDefaultInterface when there +// is no network interface available to setup the network. func (c *Do) setupNet(cid string, spec *specs.Spec) (func(), error) { dev, err := defaultDevice() if err != nil { - return nil, err + return nil, errNoDefaultInterface } peerIP, err := calculatePeerIP(c.ip) if err != nil { @@ -279,14 +295,11 @@ func (c *Do) setupNet(cid string, spec *specs.Spec) (func(), error) { return nil, err } - if spec.Linux == nil { - spec.Linux = &specs.Linux{} - } netns := specs.LinuxNamespace{ Type: specs.NetworkNamespace, Path: filepath.Join("/var/run/netns", cid), } - spec.Linux.Namespaces = append(spec.Linux.Namespaces, netns) + addNamespace(spec, netns) return func() { c.cleanupNet(cid, dev, resolvPath, hostnamePath, hostsPath) }, nil } |