kilo/cmd/kg/main.go
Lucas Servén Marín 2c74a560c4
pkg/wireguard: allow configuring MTU (#215)
This commit makes it possible to configure the MTU for the WireGuard
interface created by Kilo.

Signed-off-by: Lucas Servén Marín <lserven@gmail.com>
2021-07-16 14:23:11 +02:00

262 lines
8.6 KiB
Go

// Copyright 2019 the Kilo authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package main
import (
"errors"
"fmt"
"net"
"net/http"
"os"
"os/signal"
"strings"
"syscall"
"time"
"github.com/go-kit/kit/log"
"github.com/go-kit/kit/log/level"
"github.com/oklog/run"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/client_golang/prometheus/promhttp"
flag "github.com/spf13/pflag"
apiextensions "k8s.io/apiextensions-apiserver/pkg/client/clientset/clientset"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/tools/clientcmd"
"github.com/squat/kilo/pkg/encapsulation"
"github.com/squat/kilo/pkg/k8s"
kiloclient "github.com/squat/kilo/pkg/k8s/clientset/versioned"
"github.com/squat/kilo/pkg/mesh"
"github.com/squat/kilo/pkg/version"
"github.com/squat/kilo/pkg/wireguard"
)
const (
logLevelAll = "all"
logLevelDebug = "debug"
logLevelInfo = "info"
logLevelWarn = "warn"
logLevelError = "error"
logLevelNone = "none"
)
var (
availableBackends = strings.Join([]string{
k8s.Backend,
}, ", ")
availableCompatibilities = strings.Join([]string{
"flannel",
}, ", ")
availableEncapsulations = strings.Join([]string{
string(encapsulation.Never),
string(encapsulation.CrossSubnet),
string(encapsulation.Always),
}, ", ")
availableGranularities = strings.Join([]string{
string(mesh.LogicalGranularity),
string(mesh.FullGranularity),
}, ", ")
availableLogLevels = strings.Join([]string{
logLevelAll,
logLevelDebug,
logLevelInfo,
logLevelWarn,
logLevelError,
logLevelNone,
}, ", ")
)
// Main is the principal function for the binary, wrapped only by `main` for convenience.
func Main() error {
backend := flag.String("backend", k8s.Backend, fmt.Sprintf("The backend for the mesh. Possible values: %s", availableBackends))
cleanUpIface := flag.Bool("clean-up-interface", false, "Should Kilo delete its interface when it shuts down?")
createIface := flag.Bool("create-interface", true, "Should kilo create an interface on startup?")
cni := flag.Bool("cni", true, "Should Kilo manage the node's CNI configuration?")
cniPath := flag.String("cni-path", mesh.DefaultCNIPath, "Path to CNI config.")
compatibility := flag.String("compatibility", "", fmt.Sprintf("Should Kilo run in compatibility mode? Possible values: %s", availableCompatibilities))
encapsulate := flag.String("encapsulate", string(encapsulation.Always), fmt.Sprintf("When should Kilo encapsulate packets within a location? Possible values: %s", availableEncapsulations))
granularity := flag.String("mesh-granularity", string(mesh.LogicalGranularity), fmt.Sprintf("The granularity of the network mesh to create. Possible values: %s", availableGranularities))
kubeconfig := flag.String("kubeconfig", "", "Path to kubeconfig.")
hostname := flag.String("hostname", "", "Hostname of the node on which this process is running.")
iface := flag.String("interface", mesh.DefaultKiloInterface, "Name of the Kilo interface to use; if it does not exist, it will be created.")
listen := flag.String("listen", ":1107", "The address at which to listen for health and metrics.")
local := flag.Bool("local", true, "Should Kilo manage routes within a location?")
logLevel := flag.String("log-level", logLevelInfo, fmt.Sprintf("Log level to use. Possible values: %s", availableLogLevels))
master := flag.String("master", "", "The address of the Kubernetes API server (overrides any value in kubeconfig).")
mtu := flag.Uint("mtu", wireguard.DefaultMTU, "The MTU of the WireGuard interface created by Kilo.")
topologyLabel := flag.String("topology-label", k8s.RegionLabelKey, "Kubernetes node label used to group nodes into logical locations.")
var port uint
flag.UintVar(&port, "port", mesh.DefaultKiloPort, "The port over which WireGuard peers should communicate.")
subnet := flag.String("subnet", mesh.DefaultKiloSubnet.String(), "CIDR from which to allocate addresses for WireGuard interfaces.")
resyncPeriod := flag.Duration("resync-period", 30*time.Second, "How often should the Kilo controllers reconcile?")
printVersion := flag.Bool("version", false, "Print version and exit")
flag.Parse()
if *printVersion {
fmt.Println(version.Version)
return nil
}
_, s, err := net.ParseCIDR(*subnet)
if err != nil {
return fmt.Errorf("failed to parse %q as CIDR: %v", *subnet, err)
}
if *hostname == "" {
var err error
*hostname, err = os.Hostname()
if *hostname == "" || err != nil {
return errors.New("failed to determine hostname")
}
}
logger := log.NewJSONLogger(log.NewSyncWriter(os.Stdout))
switch *logLevel {
case logLevelAll:
logger = level.NewFilter(logger, level.AllowAll())
case logLevelDebug:
logger = level.NewFilter(logger, level.AllowDebug())
case logLevelInfo:
logger = level.NewFilter(logger, level.AllowInfo())
case logLevelWarn:
logger = level.NewFilter(logger, level.AllowWarn())
case logLevelError:
logger = level.NewFilter(logger, level.AllowError())
case logLevelNone:
logger = level.NewFilter(logger, level.AllowNone())
default:
return fmt.Errorf("log level %v unknown; possible values are: %s", *logLevel, availableLogLevels)
}
logger = log.With(logger, "ts", log.DefaultTimestampUTC)
logger = log.With(logger, "caller", log.DefaultCaller)
e := encapsulation.Strategy(*encapsulate)
switch e {
case encapsulation.Never:
case encapsulation.CrossSubnet:
case encapsulation.Always:
default:
return fmt.Errorf("encapsulation %v unknown; possible values are: %s", *encapsulate, availableEncapsulations)
}
var enc encapsulation.Encapsulator
switch *compatibility {
case "flannel":
enc = encapsulation.NewFlannel(e)
default:
enc = encapsulation.NewIPIP(e)
}
gr := mesh.Granularity(*granularity)
switch gr {
case mesh.LogicalGranularity:
case mesh.FullGranularity:
default:
return fmt.Errorf("mesh granularity %v unknown; possible values are: %s", *granularity, availableGranularities)
}
var b mesh.Backend
switch *backend {
case k8s.Backend:
config, err := clientcmd.BuildConfigFromFlags(*master, *kubeconfig)
if err != nil {
return fmt.Errorf("failed to create Kubernetes config: %v", err)
}
c := kubernetes.NewForConfigOrDie(config)
kc := kiloclient.NewForConfigOrDie(config)
ec := apiextensions.NewForConfigOrDie(config)
b = k8s.New(c, kc, ec, *topologyLabel)
default:
return fmt.Errorf("backend %v unknown; possible values are: %s", *backend, availableBackends)
}
m, err := mesh.New(b, enc, gr, *hostname, uint32(port), s, *local, *cni, *cniPath, *iface, *cleanUpIface, *createIface, *mtu, *resyncPeriod, log.With(logger, "component", "kilo"))
if err != nil {
return fmt.Errorf("failed to create Kilo mesh: %v", err)
}
r := prometheus.NewRegistry()
r.MustRegister(
prometheus.NewGoCollector(),
prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{}),
)
m.RegisterMetrics(r)
var g run.Group
{
// Run the HTTP server.
mux := http.NewServeMux()
mux.HandleFunc("/health", func(w http.ResponseWriter, _ *http.Request) {
w.WriteHeader(http.StatusOK)
})
mux.Handle("/metrics", promhttp.HandlerFor(r, promhttp.HandlerOpts{}))
l, err := net.Listen("tcp", *listen)
if err != nil {
return fmt.Errorf("failed to listen on %s: %v", *listen, err)
}
g.Add(func() error {
if err := http.Serve(l, mux); err != nil && err != http.ErrServerClosed {
return fmt.Errorf("error: server exited unexpectedly: %v", err)
}
return nil
}, func(error) {
l.Close()
})
}
{
// Start the mesh.
g.Add(func() error {
logger.Log("msg", fmt.Sprintf("Starting Kilo network mesh '%v'.", version.Version))
if err := m.Run(); err != nil {
return fmt.Errorf("error: Kilo exited unexpectedly: %v", err)
}
return nil
}, func(error) {
m.Stop()
})
}
{
// Exit gracefully on SIGINT and SIGTERM.
term := make(chan os.Signal, 1)
signal.Notify(term, syscall.SIGINT, syscall.SIGTERM)
cancel := make(chan struct{})
g.Add(func() error {
for {
select {
case <-term:
logger.Log("msg", "caught interrupt; gracefully cleaning up; see you next time!")
return nil
case <-cancel:
return nil
}
}
}, func(error) {
close(cancel)
})
}
return g.Run()
}
func main() {
if err := Main(); err != nil {
fmt.Fprintf(os.Stderr, "%v\n", err)
os.Exit(1)
}
}