func attach(args []string) error {
if len(args) < 4 {
cmdUsage("attach-container", "[--no-multicast-route] [--keep-tx-on] <container-id> <bridge-name> <mtu> <cidr>...")
}
keepTXOn := false
withMulticastRoute := true
for i := 0; i < len(args); {
switch args[i] {
case "--no-multicast-route":
withMulticastRoute = false
args = append(args[:i], args[i+1:]...)
case "--keep-tx-on":
keepTXOn = true
args = append(args[:i], args[i+1:]...)
default:
i++
}
}
pid, nsContainer, err := containerPidAndNs(args[0])
if err != nil {
return err
}
if nsHost, err := netns.GetFromPid(1); err != nil {
return fmt.Errorf("unable to open host namespace: %s", err)
} else if nsHost.Equal(nsContainer) {
return fmt.Errorf("Container is running in the host network namespace, and therefore cannot be\nconnected to weave. Perhaps the container was started with --net=host.")
}
mtu, err := strconv.Atoi(args[2])
if err != nil && args[3] != "" {
return fmt.Errorf("unable to parse mtu %q: %s", args[2], err)
}
cidrs, err := parseCIDRs(args[3:])
if err != nil {
return err
}
err = weavenet.AttachContainer(nsContainer, fmt.Sprint(pid), weavenet.VethName, args[1], mtu, withMulticastRoute, cidrs, keepTXOn)
// If we detected an error but the container has died, tell the user that instead.
if err != nil && !processExists(pid) {
err = fmt.Errorf("Container %s died", args[0])
}
return err
}
func (c *CNIPlugin) CmdAdd(args *skel.CmdArgs) error {
conf, err := loadNetConf(args.StdinData)
if err != nil {
return err
}
if conf.IsGW {
return fmt.Errorf("Gateway functionality not supported")
}
if conf.IPMasq {
return fmt.Errorf("IP Masquerading functionality not supported")
}
result, err := c.getIP(conf.IPAM.Type, args)
if err != nil {
return fmt.Errorf("unable to allocate IP address: %s", err)
}
// If config says nothing about routes or gateway, default one will be via the bridge
if result.IP4.Routes == nil && result.IP4.Gateway == nil {
bridgeIP, err := findBridgeIP(conf.BrName, result.IP4.IP)
if err == errBridgeNoIP {
bridgeArgs := *args
bridgeArgs.ContainerID = "weave:expose"
bridgeIPResult, err := c.getIP(conf.IPAM.Type, &bridgeArgs)
if err != nil {
return fmt.Errorf("unable to allocate IP address for bridge: %s", err)
}
if err := assignBridgeIP(conf.BrName, bridgeIPResult.IP4.IP); err != nil {
return fmt.Errorf("unable to assign IP address to bridge: %s", err)
}
bridgeIP = bridgeIPResult.IP4.IP.IP
} else if err != nil {
return err
}
result.IP4.Gateway = bridgeIP
}
ns, err := netns.GetFromPath(args.Netns)
if err != nil {
return err
}
defer ns.Close()
id := args.ContainerID
if len(id) < 5 {
data := make([]byte, 5)
_, err := rand.Reader.Read(data)
if err != nil {
return err
}
id = fmt.Sprintf("%x", data)
}
if err := weavenet.AttachContainer(ns, id, args.IfName, conf.BrName, conf.MTU, false, []*net.IPNet{&result.IP4.IP}, false); err != nil {
return err
}
if err := weavenet.WithNetNSLinkUnsafe(ns, args.IfName, func(link netlink.Link) error {
return setupRoutes(link, args.IfName, result.IP4.IP, result.IP4.Gateway, result.IP4.Routes)
}); err != nil {
return fmt.Errorf("error setting up routes: %s", err)
}
result.DNS = conf.DNS
return result.Print()
}
