diff options
author | Bhasker Hariharan <bhaskerh@google.com> | 2019-06-06 08:05:46 -0700 |
---|---|---|
committer | Shentubot <shentubot@google.com> | 2019-06-06 08:07:02 -0700 |
commit | 85be01b42d4ac48698d1e8f50a4cf2607a4fc50b (patch) | |
tree | 18d58e55f9c21a177ed149d460f751649df7f0e5 /runsc | |
parent | 79f7cb6c1c4c16e3aca44d7fdc8e9f2487a605cf (diff) |
Add multi-fd support to fdbased endpoint.
This allows an fdbased endpoint to have multiple underlying fd's from which
packets can be read and dispatched/written to.
This should allow for higher throughput as well as better scalability of the
network stack as number of connections increases.
Updates #231
PiperOrigin-RevId: 251852825
Diffstat (limited to 'runsc')
-rw-r--r-- | runsc/boot/config.go | 6 | ||||
-rw-r--r-- | runsc/boot/network.go | 39 | ||||
-rw-r--r-- | runsc/main.go | 25 | ||||
-rw-r--r-- | runsc/sandbox/network.go | 119 | ||||
-rw-r--r-- | runsc/test/testutil/testutil.go | 1 |
5 files changed, 123 insertions, 67 deletions
diff --git a/runsc/boot/config.go b/runsc/boot/config.go index 15f624f9b..8564c502d 100644 --- a/runsc/boot/config.go +++ b/runsc/boot/config.go @@ -221,6 +221,11 @@ type Config struct { // user, and without chrooting the sandbox process. This can be // necessary in test environments that have limited capabilities. TestOnlyAllowRunAsCurrentUserWithoutChroot bool + + // NumNetworkChannels controls the number of AF_PACKET sockets that map + // to the same underlying network device. This allows netstack to better + // scale for high throughput use cases. + NumNetworkChannels int } // ToFlags returns a slice of flags that correspond to the given Config. @@ -244,6 +249,7 @@ func (c *Config) ToFlags() []string { "--panic-signal=" + strconv.Itoa(c.PanicSignal), "--profile=" + strconv.FormatBool(c.ProfileEnable), "--net-raw=" + strconv.FormatBool(c.EnableRaw), + "--num-network-channels=" + strconv.Itoa(c.NumNetworkChannels), } if c.TestOnlyAllowRunAsCurrentUserWithoutChroot { // Only include if set since it is never to be used by users. diff --git a/runsc/boot/network.go b/runsc/boot/network.go index 0a154d90b..82c259f47 100644 --- a/runsc/boot/network.go +++ b/runsc/boot/network.go @@ -57,6 +57,10 @@ type FDBasedLink struct { Routes []Route GSOMaxSize uint32 LinkAddress []byte + + // NumChannels controls how many underlying FD's are to be used to + // create this endpoint. + NumChannels int } // LoopbackLink configures a loopback li nk. @@ -68,8 +72,9 @@ type LoopbackLink struct { // CreateLinksAndRoutesArgs are arguments to CreateLinkAndRoutes. type CreateLinksAndRoutesArgs struct { - // FilePayload contains the fds associated with the FDBasedLinks. The - // two slices must have the same length. + // FilePayload contains the fds associated with the FDBasedLinks. The + // number of fd's should match the sum of the NumChannels field of the + // FDBasedLink entries below. urpc.FilePayload LoopbackLinks []LoopbackLink @@ -95,8 +100,12 @@ func (r *Route) toTcpipRoute(id tcpip.NICID) tcpip.Route { // CreateLinksAndRoutes creates links and routes in a network stack. It should // only be called once. func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct{}) error { - if len(args.FilePayload.Files) != len(args.FDBasedLinks) { - return fmt.Errorf("FilePayload must be same length at FDBasedLinks") + wantFDs := 0 + for _, l := range args.FDBasedLinks { + wantFDs += l.NumChannels + } + if got := len(args.FilePayload.Files); got != wantFDs { + return fmt.Errorf("args.FilePayload.Files has %d FD's but we need %d entries based on FDBasedLinks", got, wantFDs) } var nicID tcpip.NICID @@ -123,20 +132,26 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct } } - for i, link := range args.FDBasedLinks { + fdOffset := 0 + for _, link := range args.FDBasedLinks { nicID++ nicids[link.Name] = nicID - // Copy the underlying FD. - oldFD := args.FilePayload.Files[i].Fd() - newFD, err := syscall.Dup(int(oldFD)) - if err != nil { - return fmt.Errorf("failed to dup FD %v: %v", oldFD, err) + FDs := []int{} + for j := 0; j < link.NumChannels; j++ { + // Copy the underlying FD. + oldFD := args.FilePayload.Files[fdOffset].Fd() + newFD, err := syscall.Dup(int(oldFD)) + if err != nil { + return fmt.Errorf("failed to dup FD %v: %v", oldFD, err) + } + FDs = append(FDs, newFD) + fdOffset++ } mac := tcpip.LinkAddress(link.LinkAddress) linkEP, err := fdbased.New(&fdbased.Options{ - FD: newFD, + FDs: FDs, MTU: uint32(link.MTU), EthernetHeader: true, Address: mac, @@ -148,7 +163,7 @@ func (n *Network) CreateLinksAndRoutes(args *CreateLinksAndRoutesArgs, _ *struct return err } - log.Infof("Enabling interface %q with id %d on addresses %+v (%v)", link.Name, nicID, link.Addresses, mac) + log.Infof("Enabling interface %q with id %d on addresses %+v (%v) w/ %d channels", link.Name, nicID, link.Addresses, mac, link.NumChannels) if err := n.createNICWithAddrs(nicID, link.Name, linkEP, link.Addresses, false /* loopback */); err != nil { return err } diff --git a/runsc/main.go b/runsc/main.go index 11bc73f75..44ad23cba 100644 --- a/runsc/main.go +++ b/runsc/main.go @@ -60,16 +60,16 @@ var ( straceLogSize = flag.Uint("strace-log-size", 1024, "default size (in bytes) to log data argument blobs") // Flags that control sandbox runtime behavior. - platform = flag.String("platform", "ptrace", "specifies which platform to use: ptrace (default), kvm") - network = flag.String("network", "sandbox", "specifies which network to use: sandbox (default), host, none. Using network inside the sandbox is more secure because it's isolated from the host network.") - gso = flag.Bool("gso", true, "enable generic segmenation offload") - fileAccess = flag.String("file-access", "exclusive", "specifies which filesystem to use for the root mount: exclusive (default), shared. Volume mounts are always shared.") - overlay = flag.Bool("overlay", false, "wrap filesystem mounts with writable overlay. All modifications are stored in memory inside the sandbox.") - watchdogAction = flag.String("watchdog-action", "log", "sets what action the watchdog takes when triggered: log (default), panic.") - panicSignal = flag.Int("panic-signal", -1, "register signal handling that panics. Usually set to SIGUSR2(12) to troubleshoot hangs. -1 disables it.") - profile = flag.Bool("profile", false, "prepares the sandbox to use Golang profiler. Note that enabling profiler loosens the seccomp protection added to the sandbox (DO NOT USE IN PRODUCTION).") - netRaw = flag.Bool("net-raw", false, "enable raw sockets. When false, raw sockets are disabled by removing CAP_NET_RAW from containers (`runsc exec` will still be able to utilize raw sockets). Raw sockets allow malicious containers to craft packets and potentially attack the network.") - + platform = flag.String("platform", "ptrace", "specifies which platform to use: ptrace (default), kvm") + network = flag.String("network", "sandbox", "specifies which network to use: sandbox (default), host, none. Using network inside the sandbox is more secure because it's isolated from the host network.") + gso = flag.Bool("gso", true, "enable generic segmenation offload") + fileAccess = flag.String("file-access", "exclusive", "specifies which filesystem to use for the root mount: exclusive (default), shared. Volume mounts are always shared.") + overlay = flag.Bool("overlay", false, "wrap filesystem mounts with writable overlay. All modifications are stored in memory inside the sandbox.") + watchdogAction = flag.String("watchdog-action", "log", "sets what action the watchdog takes when triggered: log (default), panic.") + panicSignal = flag.Int("panic-signal", -1, "register signal handling that panics. Usually set to SIGUSR2(12) to troubleshoot hangs. -1 disables it.") + profile = flag.Bool("profile", false, "prepares the sandbox to use Golang profiler. Note that enabling profiler loosens the seccomp protection added to the sandbox (DO NOT USE IN PRODUCTION).") + netRaw = flag.Bool("net-raw", false, "enable raw sockets. When false, raw sockets are disabled by removing CAP_NET_RAW from containers (`runsc exec` will still be able to utilize raw sockets). Raw sockets allow malicious containers to craft packets and potentially attack the network.") + numNetworkChannels = flag.Int("num-network-channels", 1, "number of underlying channels(FDs) to use for network link endpoints.") testOnlyAllowRunAsCurrentUserWithoutChroot = flag.Bool("TESTONLY-unsafe-nonroot", false, "TEST ONLY; do not ever use! This skips many security measures that isolate the host from the sandbox.") ) @@ -141,6 +141,10 @@ func main() { cmd.Fatalf("%v", err) } + if *numNetworkChannels <= 0 { + cmd.Fatalf("num_network_channels must be > 0, got: %d", *numNetworkChannels) + } + // Create a new Config from the flags. conf := &boot.Config{ RootDir: *rootDir, @@ -162,6 +166,7 @@ func main() { ProfileEnable: *profile, EnableRaw: *netRaw, TestOnlyAllowRunAsCurrentUserWithoutChroot: *testOnlyAllowRunAsCurrentUserWithoutChroot, + NumNetworkChannels: *numNetworkChannels, } if len(*straceSyscalls) != 0 { conf.StraceSyscalls = strings.Split(*straceSyscalls, ",") diff --git a/runsc/sandbox/network.go b/runsc/sandbox/network.go index 0460d5f1a..1fd091514 100644 --- a/runsc/sandbox/network.go +++ b/runsc/sandbox/network.go @@ -68,7 +68,7 @@ func setupNetwork(conn *urpc.Client, pid int, spec *specs.Spec, conf *boot.Confi // Build the path to the net namespace of the sandbox process. // This is what we will copy. nsPath := filepath.Join("/proc", strconv.Itoa(pid), "ns/net") - if err := createInterfacesAndRoutesFromNS(conn, nsPath, conf.GSO); err != nil { + if err := createInterfacesAndRoutesFromNS(conn, nsPath, conf.GSO, conf.NumNetworkChannels); err != nil { return fmt.Errorf("creating interfaces from net namespace %q: %v", nsPath, err) } case boot.NetworkHost: @@ -138,7 +138,7 @@ func isRootNS() (bool, error) { // createInterfacesAndRoutesFromNS scrapes the interface and routes from the // net namespace with the given path, creates them in the sandbox, and removes // them from the host. -func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, enableGSO bool) error { +func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, enableGSO bool, numNetworkChannels int) error { // Join the network namespace that we will be copying. restore, err := joinNetNS(nsPath) if err != nil { @@ -202,25 +202,6 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, enableGSO continue } - // Create the socket. - const protocol = 0x0300 // htons(ETH_P_ALL) - fd, err := syscall.Socket(syscall.AF_PACKET, syscall.SOCK_RAW, protocol) - if err != nil { - return fmt.Errorf("unable to create raw socket: %v", err) - } - deviceFile := os.NewFile(uintptr(fd), "raw-device-fd") - - // Bind to the appropriate device. - ll := syscall.SockaddrLinklayer{ - Protocol: protocol, - Ifindex: iface.Index, - Hatype: 0, // No ARP type. - Pkttype: syscall.PACKET_OTHERHOST, - } - if err := syscall.Bind(fd, &ll); err != nil { - return fmt.Errorf("unable to bind to %q: %v", iface.Name, err) - } - // Scrape the routes before removing the address, since that // will remove the routes as well. routes, def, err := routesForIface(iface) @@ -236,9 +217,10 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, enableGSO } link := boot.FDBasedLink{ - Name: iface.Name, - MTU: iface.MTU, - Routes: routes, + Name: iface.Name, + MTU: iface.MTU, + Routes: routes, + NumChannels: numNetworkChannels, } // Get the link for the interface. @@ -248,30 +230,23 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, enableGSO } link.LinkAddress = []byte(ifaceLink.Attrs().HardwareAddr) - if enableGSO { - gso, err := isGSOEnabled(fd, iface.Name) + log.Debugf("Setting up network channels") + // Create the socket for the device. + for i := 0; i < link.NumChannels; i++ { + log.Debugf("Creating Channel %d", i) + socketEntry, err := createSocket(iface, ifaceLink, enableGSO) if err != nil { - return fmt.Errorf("getting GSO for interface %q: %v", iface.Name, err) + return fmt.Errorf("failed to createSocket for %s : %v", iface.Name, err) } - if gso { - if err := syscall.SetsockoptInt(fd, syscall.SOL_PACKET, unix.PACKET_VNET_HDR, 1); err != nil { - return fmt.Errorf("unable to enable the PACKET_VNET_HDR option: %v", err) - } - link.GSOMaxSize = ifaceLink.Attrs().GSOMaxSize + if i == 0 { + link.GSOMaxSize = socketEntry.gsoMaxSize } else { - log.Infof("GSO not available in host.") + if link.GSOMaxSize != socketEntry.gsoMaxSize { + return fmt.Errorf("inconsistent gsoMaxSize %d and %d when creating multiple channels for same interface: %s", + link.GSOMaxSize, socketEntry.gsoMaxSize, iface.Name) + } } - } - - // Use SO_RCVBUFFORCE because on linux the receive buffer for an - // AF_PACKET socket is capped by "net.core.rmem_max". rmem_max - // defaults to a unusually low value of 208KB. This is too low - // for gVisor to be able to receive packets at high throughputs - // without incurring packet drops. - const rcvBufSize = 4 << 20 // 4MB. - - if err := syscall.SetsockoptInt(fd, syscall.SOL_SOCKET, syscall.SO_RCVBUFFORCE, rcvBufSize); err != nil { - return fmt.Errorf("failed to increase socket rcv buffer to %d: %v", rcvBufSize, err) + args.FilePayload.Files = append(args.FilePayload.Files, socketEntry.deviceFile) } // Collect the addresses for the interface, enable forwarding, @@ -285,7 +260,6 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, enableGSO } } - args.FilePayload.Files = append(args.FilePayload.Files, deviceFile) args.FDBasedLinks = append(args.FDBasedLinks, link) } @@ -296,6 +270,61 @@ func createInterfacesAndRoutesFromNS(conn *urpc.Client, nsPath string, enableGSO return nil } +type socketEntry struct { + deviceFile *os.File + gsoMaxSize uint32 +} + +// createSocket creates an underlying AF_PACKET socket and configures it for use by +// the sentry and returns an *os.File that wraps the underlying socket fd. +func createSocket(iface net.Interface, ifaceLink netlink.Link, enableGSO bool) (*socketEntry, error) { + // Create the socket. + const protocol = 0x0300 // htons(ETH_P_ALL) + fd, err := syscall.Socket(syscall.AF_PACKET, syscall.SOCK_RAW, protocol) + if err != nil { + return nil, fmt.Errorf("unable to create raw socket: %v", err) + } + deviceFile := os.NewFile(uintptr(fd), "raw-device-fd") + // Bind to the appropriate device. + ll := syscall.SockaddrLinklayer{ + Protocol: protocol, + Ifindex: iface.Index, + Hatype: 0, // No ARP type. + Pkttype: syscall.PACKET_OTHERHOST, + } + if err := syscall.Bind(fd, &ll); err != nil { + return nil, fmt.Errorf("unable to bind to %q: %v", iface.Name, err) + } + + gsoMaxSize := uint32(0) + if enableGSO { + gso, err := isGSOEnabled(fd, iface.Name) + if err != nil { + return nil, fmt.Errorf("getting GSO for interface %q: %v", iface.Name, err) + } + if gso { + if err := syscall.SetsockoptInt(fd, syscall.SOL_PACKET, unix.PACKET_VNET_HDR, 1); err != nil { + return nil, fmt.Errorf("unable to enable the PACKET_VNET_HDR option: %v", err) + } + gsoMaxSize = ifaceLink.Attrs().GSOMaxSize + } else { + log.Infof("GSO not available in host.") + } + } + + // Use SO_RCVBUFFORCE because on linux the receive buffer for an + // AF_PACKET socket is capped by "net.core.rmem_max". rmem_max + // defaults to a unusually low value of 208KB. This is too low + // for gVisor to be able to receive packets at high throughputs + // without incurring packet drops. + const rcvBufSize = 4 << 20 // 4MB. + + if err := syscall.SetsockoptInt(fd, syscall.SOL_SOCKET, syscall.SO_RCVBUFFORCE, rcvBufSize); err != nil { + return nil, fmt.Errorf("failed to increase socket rcv buffer to %d: %v", rcvBufSize, err) + } + return &socketEntry{deviceFile, gsoMaxSize}, nil +} + // loopbackLinks collects the links for a loopback interface. func loopbackLinks(iface net.Interface, addrs []net.Addr) ([]boot.LoopbackLink, error) { var links []boot.LoopbackLink diff --git a/runsc/test/testutil/testutil.go b/runsc/test/testutil/testutil.go index 9efb1ba8e..727b648a6 100644 --- a/runsc/test/testutil/testutil.go +++ b/runsc/test/testutil/testutil.go @@ -136,6 +136,7 @@ func TestConfig() *boot.Config { Strace: true, FileAccess: boot.FileAccessExclusive, TestOnlyAllowRunAsCurrentUserWithoutChroot: true, + NumNetworkChannels: 1, } } |