package server import ( "context" "fmt" "net" "os" "path/filepath" "strings" "time" systemd "github.com/coreos/go-systemd/daemon" "github.com/erikdubbelboer/gspt" "github.com/pkg/errors" "github.com/rancher/k3s/pkg/agent" "github.com/rancher/k3s/pkg/agent/loadbalancer" "github.com/rancher/k3s/pkg/cli/cmds" "github.com/rancher/k3s/pkg/clientaccess" "github.com/rancher/k3s/pkg/datadir" "github.com/rancher/k3s/pkg/etcd" "github.com/rancher/k3s/pkg/netutil" "github.com/rancher/k3s/pkg/rootless" "github.com/rancher/k3s/pkg/server" "github.com/rancher/k3s/pkg/token" "github.com/rancher/k3s/pkg/util" "github.com/rancher/k3s/pkg/version" "github.com/rancher/wrangler/pkg/signals" "github.com/sirupsen/logrus" "github.com/urfave/cli" utilnet "k8s.io/apimachinery/pkg/util/net" kubeapiserverflag "k8s.io/component-base/cli/flag" "k8s.io/kubernetes/pkg/controlplane" utilsnet "k8s.io/utils/net" _ "github.com/go-sql-driver/mysql" // ensure we have mysql _ "github.com/lib/pq" // ensure we have postgres _ "github.com/mattn/go-sqlite3" // ensure we have sqlite ) func Run(app *cli.Context) error { if err := cmds.InitLogging(); err != nil { return err } return run(app, &cmds.ServerConfig, server.CustomControllers{}, server.CustomControllers{}) } func RunWithControllers(app *cli.Context, leaderControllers server.CustomControllers, controllers server.CustomControllers) error { if err := cmds.InitLogging(); err != nil { return err } return run(app, &cmds.ServerConfig, leaderControllers, controllers) } func run(app *cli.Context, cfg *cmds.Server, leaderControllers server.CustomControllers, controllers server.CustomControllers) error { var ( err error ) // hide process arguments from ps output, since they may contain // database credentials or other secrets. gspt.SetProcTitle(os.Args[0] + " server") if !cfg.DisableAgent && os.Getuid() != 0 && !cfg.Rootless { return fmt.Errorf("must run as root unless --disable-agent is specified") } if cfg.Rootless { dataDir, err := datadir.LocalHome(cfg.DataDir, true) if err != nil { return err } cfg.DataDir = dataDir if err := rootless.Rootless(dataDir); err != nil { return err } } if cfg.Token == "" && cfg.ClusterSecret != "" { cfg.Token = cfg.ClusterSecret } serverConfig := server.Config{} serverConfig.DisableAgent = cfg.DisableAgent serverConfig.ControlConfig.Token = cfg.Token serverConfig.ControlConfig.AgentToken = cfg.AgentToken serverConfig.ControlConfig.JoinURL = cfg.ServerURL if cfg.AgentTokenFile != "" { serverConfig.ControlConfig.AgentToken, err = token.ReadFile(cfg.AgentTokenFile) if err != nil { return err } } if cfg.TokenFile != "" { serverConfig.ControlConfig.Token, err = token.ReadFile(cfg.TokenFile) if err != nil { return err } } serverConfig.ControlConfig.DataDir = cfg.DataDir serverConfig.ControlConfig.KubeConfigOutput = cfg.KubeConfigOutput serverConfig.ControlConfig.KubeConfigMode = cfg.KubeConfigMode serverConfig.Rootless = cfg.Rootless serverConfig.ControlConfig.SANs = cfg.TLSSan serverConfig.ControlConfig.BindAddress = cfg.BindAddress serverConfig.ControlConfig.SupervisorPort = cfg.SupervisorPort serverConfig.ControlConfig.HTTPSPort = cfg.HTTPSPort serverConfig.ControlConfig.APIServerPort = cfg.APIServerPort serverConfig.ControlConfig.APIServerBindAddress = cfg.APIServerBindAddress serverConfig.ControlConfig.ExtraAPIArgs = cfg.ExtraAPIArgs serverConfig.ControlConfig.ExtraControllerArgs = cfg.ExtraControllerArgs serverConfig.ControlConfig.ExtraSchedulerAPIArgs = cfg.ExtraSchedulerArgs serverConfig.ControlConfig.ClusterDomain = cfg.ClusterDomain serverConfig.ControlConfig.Datastore.Endpoint = cfg.DatastoreEndpoint serverConfig.ControlConfig.Datastore.BackendTLSConfig.CAFile = cfg.DatastoreCAFile serverConfig.ControlConfig.Datastore.BackendTLSConfig.CertFile = cfg.DatastoreCertFile serverConfig.ControlConfig.Datastore.BackendTLSConfig.KeyFile = cfg.DatastoreKeyFile serverConfig.ControlConfig.AdvertiseIP = cfg.AdvertiseIP serverConfig.ControlConfig.AdvertisePort = cfg.AdvertisePort serverConfig.ControlConfig.FlannelBackend = cfg.FlannelBackend serverConfig.ControlConfig.ExtraCloudControllerArgs = cfg.ExtraCloudControllerArgs serverConfig.ControlConfig.DisableCCM = cfg.DisableCCM serverConfig.ControlConfig.DisableNPC = cfg.DisableNPC serverConfig.ControlConfig.DisableHelmController = cfg.DisableHelmController serverConfig.ControlConfig.DisableKubeProxy = cfg.DisableKubeProxy serverConfig.ControlConfig.DisableETCD = cfg.DisableETCD serverConfig.ControlConfig.DisableAPIServer = cfg.DisableAPIServer serverConfig.ControlConfig.DisableScheduler = cfg.DisableScheduler serverConfig.ControlConfig.DisableControllerManager = cfg.DisableControllerManager serverConfig.ControlConfig.ClusterInit = cfg.ClusterInit serverConfig.ControlConfig.EncryptSecrets = cfg.EncryptSecrets serverConfig.ControlConfig.EtcdExposeMetrics = cfg.EtcdExposeMetrics serverConfig.ControlConfig.EtcdDisableSnapshots = cfg.EtcdDisableSnapshots if !cfg.EtcdDisableSnapshots { serverConfig.ControlConfig.EtcdSnapshotName = cfg.EtcdSnapshotName serverConfig.ControlConfig.EtcdSnapshotCron = cfg.EtcdSnapshotCron serverConfig.ControlConfig.EtcdSnapshotDir = cfg.EtcdSnapshotDir serverConfig.ControlConfig.EtcdSnapshotRetention = cfg.EtcdSnapshotRetention serverConfig.ControlConfig.EtcdS3 = cfg.EtcdS3 serverConfig.ControlConfig.EtcdS3Endpoint = cfg.EtcdS3Endpoint serverConfig.ControlConfig.EtcdS3EndpointCA = cfg.EtcdS3EndpointCA serverConfig.ControlConfig.EtcdS3SkipSSLVerify = cfg.EtcdS3SkipSSLVerify serverConfig.ControlConfig.EtcdS3AccessKey = cfg.EtcdS3AccessKey serverConfig.ControlConfig.EtcdS3SecretKey = cfg.EtcdS3SecretKey serverConfig.ControlConfig.EtcdS3BucketName = cfg.EtcdS3BucketName serverConfig.ControlConfig.EtcdS3Region = cfg.EtcdS3Region serverConfig.ControlConfig.EtcdS3Folder = cfg.EtcdS3Folder } else { logrus.Info("ETCD snapshots are disabled") } if cfg.ClusterResetRestorePath != "" && !cfg.ClusterReset { return errors.New("invalid flag use; --cluster-reset required with --cluster-reset-restore-path") } // make sure components are disabled so we only perform a restore // and bail out if cfg.ClusterResetRestorePath != "" && cfg.ClusterReset { serverConfig.ControlConfig.ClusterInit = true serverConfig.ControlConfig.DisableAPIServer = true serverConfig.ControlConfig.DisableControllerManager = true serverConfig.ControlConfig.DisableScheduler = true serverConfig.ControlConfig.DisableCCM = true // delete local loadbalancers state for apiserver and supervisor servers loadbalancer.ResetLoadBalancer(filepath.Join(cfg.DataDir, "agent"), loadbalancer.SupervisorServiceName) loadbalancer.ResetLoadBalancer(filepath.Join(cfg.DataDir, "agent"), loadbalancer.APIServerServiceName) } serverConfig.ControlConfig.ClusterReset = cfg.ClusterReset serverConfig.ControlConfig.ClusterResetRestorePath = cfg.ClusterResetRestorePath serverConfig.ControlConfig.SystemDefaultRegistry = cfg.SystemDefaultRegistry if serverConfig.ControlConfig.SupervisorPort == 0 { serverConfig.ControlConfig.SupervisorPort = serverConfig.ControlConfig.HTTPSPort } if serverConfig.ControlConfig.DisableETCD && serverConfig.ControlConfig.JoinURL == "" { return errors.New("invalid flag use; --server is required with --disable-etcd") } if serverConfig.ControlConfig.DisableAPIServer { // Servers without a local apiserver need to connect to the apiserver via the proxy load-balancer. serverConfig.ControlConfig.APIServerPort = cmds.AgentConfig.LBServerPort // If the supervisor and externally-facing apiserver are not on the same port, the proxy will // have a separate load-balancer for the apiserver that we need to use instead. if serverConfig.ControlConfig.SupervisorPort != serverConfig.ControlConfig.HTTPSPort { serverConfig.ControlConfig.APIServerPort = cmds.AgentConfig.LBServerPort - 1 } } if cmds.AgentConfig.FlannelIface != "" && len(cmds.AgentConfig.NodeIP) == 0 { cmds.AgentConfig.NodeIP.Set(netutil.GetIPFromInterface(cmds.AgentConfig.FlannelIface)) } if serverConfig.ControlConfig.PrivateIP == "" && len(cmds.AgentConfig.NodeIP) != 0 { // ignoring the error here is fine since etcd will fall back to the interface's IPv4 address serverConfig.ControlConfig.PrivateIP, _ = util.GetFirst4String(cmds.AgentConfig.NodeIP) } // if not set, try setting advertise-ip from agent node-external-ip if serverConfig.ControlConfig.AdvertiseIP == "" && len(cmds.AgentConfig.NodeExternalIP) != 0 { serverConfig.ControlConfig.AdvertiseIP, _ = util.GetFirst4String(cmds.AgentConfig.NodeExternalIP) } // if not set, try setting advertise-up from agent node-ip if serverConfig.ControlConfig.AdvertiseIP == "" && len(cmds.AgentConfig.NodeIP) != 0 { serverConfig.ControlConfig.AdvertiseIP, _ = util.GetFirst4String(cmds.AgentConfig.NodeIP) } // if we ended up with any advertise-ips, ensure they're added to the SAN list; // note that kube-apiserver does not support dual-stack advertise-ip as of 1.21.0: /// https://github.com/kubernetes/kubeadm/issues/1612#issuecomment-772583989 if serverConfig.ControlConfig.AdvertiseIP != "" { serverConfig.ControlConfig.SANs = append(serverConfig.ControlConfig.SANs, serverConfig.ControlConfig.AdvertiseIP) } // Ensure that we add the localhost name/ip and node name/ip to the SAN list. This list is shared by the // certs for the supervisor, kube-apiserver cert, and etcd. DNS entries for the in-cluster kubernetes // service endpoint are added later when the certificates are created. nodeName, nodeIPs, err := util.GetHostnameAndIPs(cmds.AgentConfig.NodeName, cmds.AgentConfig.NodeIP) if err != nil { return err } serverConfig.ControlConfig.SANs = append(serverConfig.ControlConfig.SANs, "127.0.0.1", "localhost", nodeName) for _, ip := range nodeIPs { serverConfig.ControlConfig.SANs = append(serverConfig.ControlConfig.SANs, ip.String()) } // configure ClusterIPRanges if len(cmds.ServerConfig.ClusterCIDR) == 0 { cmds.ServerConfig.ClusterCIDR.Set("10.42.0.0/16") } for _, cidr := range cmds.ServerConfig.ClusterCIDR { for _, v := range strings.Split(cidr, ",") { _, parsed, err := net.ParseCIDR(v) if err != nil { return errors.Wrapf(err, "invalid cluster-cidr %s", v) } serverConfig.ControlConfig.ClusterIPRanges = append(serverConfig.ControlConfig.ClusterIPRanges, parsed) } } // set ClusterIPRange to the first IPv4 block, for legacy clients clusterIPRange, err := util.GetFirst4Net(serverConfig.ControlConfig.ClusterIPRanges) if err != nil { return errors.Wrap(err, "cannot configure IPv4 cluster-cidr") } serverConfig.ControlConfig.ClusterIPRange = clusterIPRange // configure ServiceIPRanges if len(cmds.ServerConfig.ServiceCIDR) == 0 { cmds.ServerConfig.ServiceCIDR.Set("10.43.0.0/16") } for _, cidr := range cmds.ServerConfig.ServiceCIDR { for _, v := range strings.Split(cidr, ",") { _, parsed, err := net.ParseCIDR(v) if err != nil { return errors.Wrapf(err, "invalid service-cidr %s", v) } serverConfig.ControlConfig.ServiceIPRanges = append(serverConfig.ControlConfig.ServiceIPRanges, parsed) } } // set ServiceIPRange to the first IPv4 block, for legacy clients serviceIPRange, err := util.GetFirst4Net(serverConfig.ControlConfig.ServiceIPRanges) if err != nil { return errors.Wrap(err, "cannot configure IPv4 service-cidr") } serverConfig.ControlConfig.ServiceIPRange = serviceIPRange serverConfig.ControlConfig.ServiceNodePortRange, err = utilnet.ParsePortRange(cfg.ServiceNodePortRange) if err != nil { return errors.Wrapf(err, "invalid port range %s", cfg.ServiceNodePortRange) } // the apiserver service does not yet support dual-stack operation _, apiServerServiceIP, err := controlplane.ServiceIPRange(*serverConfig.ControlConfig.ServiceIPRange) if err != nil { return err } serverConfig.ControlConfig.SANs = append(serverConfig.ControlConfig.SANs, apiServerServiceIP.String()) // If cluster-dns CLI arg is not set, we set ClusterDNS address to be the first IPv4 ServiceCIDR network + 10, // i.e. when you set service-cidr to 192.168.0.0/16 and don't provide cluster-dns, it will be set to 192.168.0.10 // If there are no IPv4 ServiceCIDRs, an error will be raised. if len(cmds.ServerConfig.ClusterDNS) == 0 { clusterDNS, err := utilsnet.GetIndexedIP(serverConfig.ControlConfig.ServiceIPRange, 10) if err != nil { return errors.Wrap(err, "cannot configure default cluster-dns address") } serverConfig.ControlConfig.ClusterDNS = clusterDNS serverConfig.ControlConfig.ClusterDNSs = []net.IP{serverConfig.ControlConfig.ClusterDNS} } else { for _, ip := range cmds.ServerConfig.ClusterDNS { for _, v := range strings.Split(ip, ",") { parsed := net.ParseIP(v) if parsed == nil { return fmt.Errorf("invalid cluster-dns address %s", v) } serverConfig.ControlConfig.ClusterDNSs = append(serverConfig.ControlConfig.ClusterDNSs, parsed) } } // Set ClusterDNS to the first IPv4 address, for legacy clients clusterDNS, err := util.GetFirst4(serverConfig.ControlConfig.ClusterDNSs) if err != nil { return errors.Wrap(err, "cannot configure IPv4 cluster-dns address") } serverConfig.ControlConfig.ClusterDNS = clusterDNS } if err := validateNetworkConfiguration(serverConfig); err != nil { return err } if cfg.DefaultLocalStoragePath == "" { dataDir, err := datadir.LocalHome(cfg.DataDir, false) if err != nil { return err } serverConfig.ControlConfig.DefaultLocalStoragePath = filepath.Join(dataDir, "/storage") } else { serverConfig.ControlConfig.DefaultLocalStoragePath = cfg.DefaultLocalStoragePath } serverConfig.ControlConfig.Skips = map[string]bool{} for _, noDeploy := range app.StringSlice("no-deploy") { for _, v := range strings.Split(noDeploy, ",") { v = strings.TrimSpace(v) serverConfig.ControlConfig.Skips[v] = true } } serverConfig.ControlConfig.Disables = map[string]bool{} for _, disable := range app.StringSlice("disable") { for _, v := range strings.Split(disable, ",") { v = strings.TrimSpace(v) serverConfig.ControlConfig.Skips[v] = true serverConfig.ControlConfig.Disables[v] = true } } if serverConfig.ControlConfig.Skips["servicelb"] { serverConfig.DisableServiceLB = true } if serverConfig.ControlConfig.DisableCCM { serverConfig.ControlConfig.Skips["ccm"] = true serverConfig.ControlConfig.Disables["ccm"] = true } tlsMinVersionArg := getArgValueFromList("tls-min-version", cfg.ExtraAPIArgs) serverConfig.ControlConfig.TLSMinVersion, err = kubeapiserverflag.TLSVersion(tlsMinVersionArg) if err != nil { return errors.Wrap(err, "invalid tls-min-version") } serverConfig.StartupHooks = append(serverConfig.StartupHooks, cfg.StartupHooks...) serverConfig.LeaderControllers = append(serverConfig.LeaderControllers, leaderControllers...) serverConfig.Controllers = append(serverConfig.Controllers, controllers...) // TLS config based on mozilla ssl-config generator // https://ssl-config.mozilla.org/#server=golang&version=1.13.6&config=intermediate&guideline=5.4 // Need to disable the TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 Cipher for TLS1.2 tlsCipherSuitesArg := getArgValueFromList("tls-cipher-suites", cfg.ExtraAPIArgs) tlsCipherSuites := strings.Split(tlsCipherSuitesArg, ",") for i := range tlsCipherSuites { tlsCipherSuites[i] = strings.TrimSpace(tlsCipherSuites[i]) } if len(tlsCipherSuites) == 0 || tlsCipherSuites[0] == "" { tlsCipherSuites = []string{ "TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384", "TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384", "TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256", "TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256", "TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305", "TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305", } } serverConfig.ControlConfig.TLSCipherSuites, err = kubeapiserverflag.TLSCipherSuites(tlsCipherSuites) if err != nil { return errors.Wrap(err, "invalid tls-cipher-suites") } logrus.Info("Starting " + version.Program + " " + app.App.Version) notifySocket := os.Getenv("NOTIFY_SOCKET") ctx := signals.SetupSignalHandler(context.Background()) if err := server.StartServer(ctx, &serverConfig, cfg); err != nil { return err } go func() { if !serverConfig.ControlConfig.DisableAPIServer { <-serverConfig.ControlConfig.Runtime.APIServerReady logrus.Info("Kube API server is now running") } else { <-serverConfig.ControlConfig.Runtime.ETCDReady logrus.Info("ETCD server is now running") } logrus.Info(version.Program + " is up and running") if (cfg.DisableAgent || cfg.DisableAPIServer) && notifySocket != "" { os.Setenv("NOTIFY_SOCKET", notifySocket) systemd.SdNotify(true, "READY=1\n") } }() if cfg.DisableAgent { <-ctx.Done() return nil } ip := serverConfig.ControlConfig.BindAddress if ip == "" { ip = "127.0.0.1" } url := fmt.Sprintf("https://%s:%d", ip, serverConfig.ControlConfig.SupervisorPort) token, err := clientaccess.FormatToken(serverConfig.ControlConfig.Runtime.AgentToken, serverConfig.ControlConfig.Runtime.ServerCA) if err != nil { return err } agentConfig := cmds.AgentConfig agentConfig.Debug = app.GlobalBool("debug") agentConfig.DataDir = filepath.Dir(serverConfig.ControlConfig.DataDir) agentConfig.ServerURL = url agentConfig.Token = token agentConfig.DisableLoadBalancer = !serverConfig.ControlConfig.DisableAPIServer agentConfig.ETCDAgent = serverConfig.ControlConfig.DisableAPIServer agentConfig.ClusterReset = serverConfig.ControlConfig.ClusterReset agentConfig.Rootless = cfg.Rootless if agentConfig.Rootless { // let agent specify Rootless kubelet flags, but not unshare twice agentConfig.RootlessAlreadyUnshared = true } if serverConfig.ControlConfig.DisableAPIServer { // initialize the apiAddress Channel for receiving the api address from etcd agentConfig.APIAddressCh = make(chan string, 1) setAPIAddressChannel(ctx, &serverConfig, &agentConfig) defer close(agentConfig.APIAddressCh) } return agent.Run(ctx, agentConfig) } // validateNetworkConfig ensures that the network configuration values make sense. func validateNetworkConfiguration(serverConfig server.Config) error { // Dual-stack operation requires fairly extensive manual configuration at the moment - do some // preflight checks to make sure that the user isn't trying to use flannel/npc, or trying to // enable dual-stack DNS (which we don't currently support since it's not easy to template) dualCluster, err := utilsnet.IsDualStackCIDRs(serverConfig.ControlConfig.ClusterIPRanges) if err != nil { return errors.Wrap(err, "failed to validate cluster-cidr") } dualService, err := utilsnet.IsDualStackCIDRs(serverConfig.ControlConfig.ServiceIPRanges) if err != nil { return errors.Wrap(err, "failed to validate service-cidr") } dualDNS, err := utilsnet.IsDualStackIPs(serverConfig.ControlConfig.ClusterDNSs) if err != nil { return errors.Wrap(err, "failed to validate cluster-dns") } if (serverConfig.ControlConfig.FlannelBackend != "none" || serverConfig.ControlConfig.DisableNPC == false) && (dualCluster || dualService) { return errors.New("flannel CNI and network policy enforcement are not compatible with dual-stack operation; server must be restarted with --flannel-backend=none --disable-network-policy and an alternative CNI plugin deployed") } if dualDNS == true { return errors.New("dual-stack cluster-dns is not supported") } return nil } func getArgValueFromList(searchArg string, argList []string) string { var value string for _, arg := range argList { splitArg := strings.SplitN(arg, "=", 2) if splitArg[0] == searchArg { value = splitArg[1] // break if we found our value break } } return value } // setAPIAddressChannel will try to get the api address key from etcd and when it succeed it will // set the APIAddressCh channel with its value, the function works for both k3s and rke2 in case // of k3s we block returning back to the agent.Run until we get the api address, however in rke2 // the code will not block operation and will run the operation in a goroutine func setAPIAddressChannel(ctx context.Context, serverConfig *server.Config, agentConfig *cmds.Agent) { // start a goroutine to check for the server ip if set from etcd in case of rke2 if serverConfig.ControlConfig.HTTPSPort != serverConfig.ControlConfig.SupervisorPort { go getAPIAddressFromEtcd(ctx, serverConfig, agentConfig) return } getAPIAddressFromEtcd(ctx, serverConfig, agentConfig) } func getAPIAddressFromEtcd(ctx context.Context, serverConfig *server.Config, agentConfig *cmds.Agent) { t := time.NewTicker(5 * time.Second) defer t.Stop() for range t.C { serverAddress, err := etcd.GetAPIServerURLFromETCD(ctx, &serverConfig.ControlConfig) if err == nil { agentConfig.ServerURL = "https://" + serverAddress agentConfig.APIAddressCh <- agentConfig.ServerURL break } logrus.Warn(err) } }