package deps import ( "crypto" cryptorand "crypto/rand" "crypto/sha256" "crypto/x509" b64 "encoding/base64" "encoding/hex" "encoding/json" "errors" "fmt" "io/ioutil" "net" "os" "path/filepath" "strings" "text/template" "time" "github.com/k3s-io/k3s/pkg/clientaccess" "github.com/k3s-io/k3s/pkg/daemons/config" "github.com/k3s-io/k3s/pkg/passwd" "github.com/k3s-io/k3s/pkg/token" "github.com/k3s-io/k3s/pkg/util" "github.com/k3s-io/k3s/pkg/version" certutil "github.com/rancher/dynamiclistener/cert" "github.com/sirupsen/logrus" metav1 "k8s.io/apimachinery/pkg/apis/meta/v1" "k8s.io/apimachinery/pkg/util/sets" apiserverconfigv1 "k8s.io/apiserver/pkg/apis/config/v1" "k8s.io/apiserver/pkg/authentication/user" ) const ( ipsecTokenSize = 48 aescbcKeySize = 32 RequestHeaderCN = "system:auth-proxy" ) var ( kubeconfigTemplate = template.Must(template.New("kubeconfig").Parse(`apiVersion: v1 clusters: - cluster: server: {{.URL}} certificate-authority: {{.CACert}} name: local contexts: - context: cluster: local namespace: default user: user name: Default current-context: Default kind: Config preferences: {} users: - name: user user: client-certificate: {{.ClientCert}} client-key: {{.ClientKey}} `)) ) func migratePassword(p *passwd.Passwd) error { server, _ := p.Pass("server") node, _ := p.Pass("node") if server == "" && node != "" { return p.EnsureUser("server", version.Program+":server", node) } return nil } func KubeConfig(dest, url, caCert, clientCert, clientKey string) error { data := struct { URL string CACert string ClientCert string ClientKey string }{ URL: url, CACert: caCert, ClientCert: clientCert, ClientKey: clientKey, } output, err := os.Create(dest) if err != nil { return err } defer output.Close() return kubeconfigTemplate.Execute(output, &data) } // CreateRuntimeCertFiles is responsible for filling out all the // .crt and .key filenames for a ControlRuntime. func CreateRuntimeCertFiles(config *config.Control) { runtime := config.Runtime runtime.ClientCA = filepath.Join(config.DataDir, "tls", "client-ca.crt") runtime.ClientCAKey = filepath.Join(config.DataDir, "tls", "client-ca.key") runtime.ServerCA = filepath.Join(config.DataDir, "tls", "server-ca.crt") runtime.ServerCAKey = filepath.Join(config.DataDir, "tls", "server-ca.key") runtime.RequestHeaderCA = filepath.Join(config.DataDir, "tls", "request-header-ca.crt") runtime.RequestHeaderCAKey = filepath.Join(config.DataDir, "tls", "request-header-ca.key") runtime.IPSECKey = filepath.Join(config.DataDir, "cred", "ipsec.psk") runtime.ServiceKey = filepath.Join(config.DataDir, "tls", "service.key") runtime.PasswdFile = filepath.Join(config.DataDir, "cred", "passwd") runtime.NodePasswdFile = filepath.Join(config.DataDir, "cred", "node-passwd") runtime.KubeConfigAdmin = filepath.Join(config.DataDir, "cred", "admin.kubeconfig") runtime.KubeConfigController = filepath.Join(config.DataDir, "cred", "controller.kubeconfig") runtime.KubeConfigScheduler = filepath.Join(config.DataDir, "cred", "scheduler.kubeconfig") runtime.KubeConfigAPIServer = filepath.Join(config.DataDir, "cred", "api-server.kubeconfig") runtime.KubeConfigCloudController = filepath.Join(config.DataDir, "cred", "cloud-controller.kubeconfig") runtime.ClientAdminCert = filepath.Join(config.DataDir, "tls", "client-admin.crt") runtime.ClientAdminKey = filepath.Join(config.DataDir, "tls", "client-admin.key") runtime.ClientControllerCert = filepath.Join(config.DataDir, "tls", "client-controller.crt") runtime.ClientControllerKey = filepath.Join(config.DataDir, "tls", "client-controller.key") runtime.ClientCloudControllerCert = filepath.Join(config.DataDir, "tls", "client-"+version.Program+"-cloud-controller.crt") runtime.ClientCloudControllerKey = filepath.Join(config.DataDir, "tls", "client-"+version.Program+"-cloud-controller.key") runtime.ClientSchedulerCert = filepath.Join(config.DataDir, "tls", "client-scheduler.crt") runtime.ClientSchedulerKey = filepath.Join(config.DataDir, "tls", "client-scheduler.key") runtime.ClientKubeAPICert = filepath.Join(config.DataDir, "tls", "client-kube-apiserver.crt") runtime.ClientKubeAPIKey = filepath.Join(config.DataDir, "tls", "client-kube-apiserver.key") runtime.ClientKubeProxyCert = filepath.Join(config.DataDir, "tls", "client-kube-proxy.crt") runtime.ClientKubeProxyKey = filepath.Join(config.DataDir, "tls", "client-kube-proxy.key") runtime.ClientK3sControllerCert = filepath.Join(config.DataDir, "tls", "client-"+version.Program+"-controller.crt") runtime.ClientK3sControllerKey = filepath.Join(config.DataDir, "tls", "client-"+version.Program+"-controller.key") runtime.ServingKubeAPICert = filepath.Join(config.DataDir, "tls", "serving-kube-apiserver.crt") runtime.ServingKubeAPIKey = filepath.Join(config.DataDir, "tls", "serving-kube-apiserver.key") runtime.ClientKubeletKey = filepath.Join(config.DataDir, "tls", "client-kubelet.key") runtime.ServingKubeletKey = filepath.Join(config.DataDir, "tls", "serving-kubelet.key") runtime.ClientAuthProxyCert = filepath.Join(config.DataDir, "tls", "client-auth-proxy.crt") runtime.ClientAuthProxyKey = filepath.Join(config.DataDir, "tls", "client-auth-proxy.key") runtime.ETCDServerCA = filepath.Join(config.DataDir, "tls", "etcd", "server-ca.crt") runtime.ETCDServerCAKey = filepath.Join(config.DataDir, "tls", "etcd", "server-ca.key") runtime.ETCDPeerCA = filepath.Join(config.DataDir, "tls", "etcd", "peer-ca.crt") runtime.ETCDPeerCAKey = filepath.Join(config.DataDir, "tls", "etcd", "peer-ca.key") runtime.ServerETCDCert = filepath.Join(config.DataDir, "tls", "etcd", "server-client.crt") runtime.ServerETCDKey = filepath.Join(config.DataDir, "tls", "etcd", "server-client.key") runtime.PeerServerClientETCDCert = filepath.Join(config.DataDir, "tls", "etcd", "peer-server-client.crt") runtime.PeerServerClientETCDKey = filepath.Join(config.DataDir, "tls", "etcd", "peer-server-client.key") runtime.ClientETCDCert = filepath.Join(config.DataDir, "tls", "etcd", "client.crt") runtime.ClientETCDKey = filepath.Join(config.DataDir, "tls", "etcd", "client.key") if config.EncryptSecrets { runtime.EncryptionConfig = filepath.Join(config.DataDir, "cred", "encryption-config.json") runtime.EncryptionHash = filepath.Join(config.DataDir, "cred", "encryption-state.json") } } // GenServerDeps is responsible for generating the cluster dependencies // needed to successfully bootstrap a cluster. func GenServerDeps(config *config.Control) error { runtime := config.Runtime if err := genCerts(config); err != nil { return err } if err := genServiceAccount(runtime); err != nil { return err } if err := genUsers(config); err != nil { return err } if err := genEncryptedNetworkInfo(config); err != nil { return err } if err := genEncryptionConfigAndState(config); err != nil { return err } return readTokens(runtime) } func readTokens(runtime *config.ControlRuntime) error { tokens, err := passwd.Read(runtime.PasswdFile) if err != nil { return err } if nodeToken, ok := tokens.Pass("node"); ok { runtime.AgentToken = "node:" + nodeToken } if serverToken, ok := tokens.Pass("server"); ok { runtime.ServerToken = "server:" + serverToken } return nil } func getNodePass(config *config.Control, serverPass string) string { if config.AgentToken == "" { if _, passwd, ok := clientaccess.ParseUsernamePassword(serverPass); ok { return passwd } return serverPass } return config.AgentToken } func genUsers(config *config.Control) error { runtime := config.Runtime passwd, err := passwd.Read(runtime.PasswdFile) if err != nil { return err } if err := migratePassword(passwd); err != nil { return err } serverPass, err := getServerPass(passwd, config) if err != nil { return err } nodePass := getNodePass(config, serverPass) if err := passwd.EnsureUser("node", version.Program+":agent", nodePass); err != nil { return err } if err := passwd.EnsureUser("server", version.Program+":server", serverPass); err != nil { return err } return passwd.Write(runtime.PasswdFile) } func genEncryptedNetworkInfo(controlConfig *config.Control) error { runtime := controlConfig.Runtime if s, err := os.Stat(runtime.IPSECKey); err == nil && s.Size() > 0 { psk, err := ioutil.ReadFile(runtime.IPSECKey) if err != nil { return err } controlConfig.IPSECPSK = strings.TrimSpace(string(psk)) return nil } psk, err := token.Random(ipsecTokenSize) if err != nil { return err } controlConfig.IPSECPSK = psk return ioutil.WriteFile(runtime.IPSECKey, []byte(psk+"\n"), 0600) } func getServerPass(passwd *passwd.Passwd, config *config.Control) (string, error) { var ( err error ) serverPass := config.Token if serverPass == "" { serverPass, _ = passwd.Pass("server") } if serverPass == "" { serverPass, err = token.Random(16) if err != nil { return "", err } } return serverPass, nil } func genCerts(config *config.Control) error { if err := genClientCerts(config); err != nil { return err } if err := genServerCerts(config); err != nil { return err } if err := genRequestHeaderCerts(config); err != nil { return err } return genETCDCerts(config) } func getSigningCertFactory(regen bool, altNames *certutil.AltNames, extKeyUsage []x509.ExtKeyUsage, caCertFile, caKeyFile string) signedCertFactory { return func(commonName string, organization []string, certFile, keyFile string) (bool, error) { return createClientCertKey(regen, commonName, organization, altNames, extKeyUsage, caCertFile, caKeyFile, certFile, keyFile) } } func genClientCerts(config *config.Control) error { runtime := config.Runtime regen, err := createSigningCertKey(version.Program+"-client", runtime.ClientCA, runtime.ClientCAKey) if err != nil { return err } factory := getSigningCertFactory(regen, nil, []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth}, runtime.ClientCA, runtime.ClientCAKey) var certGen bool IPv6OnlyService, _ := util.IsIPv6OnlyCIDRs(config.ServiceIPRanges) ip := "127.0.0.1" if IPv6OnlyService { ip = "[::1]" } apiEndpoint := fmt.Sprintf("https://%s:%d", ip, config.APIServerPort) certGen, err = factory("system:admin", []string{user.SystemPrivilegedGroup}, runtime.ClientAdminCert, runtime.ClientAdminKey) if err != nil { return err } if certGen { if err := KubeConfig(runtime.KubeConfigAdmin, apiEndpoint, runtime.ServerCA, runtime.ClientAdminCert, runtime.ClientAdminKey); err != nil { return err } } certGen, err = factory(user.KubeControllerManager, nil, runtime.ClientControllerCert, runtime.ClientControllerKey) if err != nil { return err } if certGen { if err := KubeConfig(runtime.KubeConfigController, apiEndpoint, runtime.ServerCA, runtime.ClientControllerCert, runtime.ClientControllerKey); err != nil { return err } } certGen, err = factory(user.KubeScheduler, nil, runtime.ClientSchedulerCert, runtime.ClientSchedulerKey) if err != nil { return err } if certGen { if err := KubeConfig(runtime.KubeConfigScheduler, apiEndpoint, runtime.ServerCA, runtime.ClientSchedulerCert, runtime.ClientSchedulerKey); err != nil { return err } } certGen, err = factory(user.APIServerUser, []string{user.SystemPrivilegedGroup}, runtime.ClientKubeAPICert, runtime.ClientKubeAPIKey) if err != nil { return err } if certGen { if err := KubeConfig(runtime.KubeConfigAPIServer, apiEndpoint, runtime.ServerCA, runtime.ClientKubeAPICert, runtime.ClientKubeAPIKey); err != nil { return err } } if _, err = factory(user.KubeProxy, nil, runtime.ClientKubeProxyCert, runtime.ClientKubeProxyKey); err != nil { return err } // This user (system:k3s-controller by default) must be bound to a role in rolebindings.yaml or the downstream equivalent if _, err = factory("system:"+version.Program+"-controller", nil, runtime.ClientK3sControllerCert, runtime.ClientK3sControllerKey); err != nil { return err } if _, _, err := certutil.LoadOrGenerateKeyFile(runtime.ClientKubeletKey, regen); err != nil { return err } certGen, err = factory(version.Program+"-cloud-controller-manager", nil, runtime.ClientCloudControllerCert, runtime.ClientCloudControllerKey) if err != nil { return err } if certGen { if err := KubeConfig(runtime.KubeConfigCloudController, apiEndpoint, runtime.ServerCA, runtime.ClientCloudControllerCert, runtime.ClientCloudControllerKey); err != nil { return err } } return nil } func genServerCerts(config *config.Control) error { runtime := config.Runtime regen, err := createServerSigningCertKey(config) if err != nil { return err } altNames := &certutil.AltNames{ DNSNames: []string{"kubernetes", "kubernetes.default", "kubernetes.default.svc", "kubernetes.default.svc." + config.ClusterDomain}, } addSANs(altNames, config.SANs) if _, err := createClientCertKey(regen, "kube-apiserver", nil, altNames, []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth}, runtime.ServerCA, runtime.ServerCAKey, runtime.ServingKubeAPICert, runtime.ServingKubeAPIKey); err != nil { return err } if _, _, err := certutil.LoadOrGenerateKeyFile(runtime.ServingKubeletKey, regen); err != nil { return err } return nil } func genETCDCerts(config *config.Control) error { runtime := config.Runtime regen, err := createSigningCertKey("etcd-server", runtime.ETCDServerCA, runtime.ETCDServerCAKey) if err != nil { return err } altNames := &certutil.AltNames{} addSANs(altNames, config.SANs) if _, err := createClientCertKey(regen, "etcd-server", nil, altNames, []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth, x509.ExtKeyUsageClientAuth}, runtime.ETCDServerCA, runtime.ETCDServerCAKey, runtime.ServerETCDCert, runtime.ServerETCDKey); err != nil { return err } if _, err := createClientCertKey(regen, "etcd-client", nil, nil, []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth}, runtime.ETCDServerCA, runtime.ETCDServerCAKey, runtime.ClientETCDCert, runtime.ClientETCDKey); err != nil { return err } regen, err = createSigningCertKey("etcd-peer", runtime.ETCDPeerCA, runtime.ETCDPeerCAKey) if err != nil { return err } if _, err := createClientCertKey(regen, "etcd-peer", nil, altNames, []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth, x509.ExtKeyUsageClientAuth}, runtime.ETCDPeerCA, runtime.ETCDPeerCAKey, runtime.PeerServerClientETCDCert, runtime.PeerServerClientETCDKey); err != nil { return err } return nil } func genRequestHeaderCerts(config *config.Control) error { runtime := config.Runtime regen, err := createSigningCertKey(version.Program+"-request-header", runtime.RequestHeaderCA, runtime.RequestHeaderCAKey) if err != nil { return err } if _, err := createClientCertKey(regen, RequestHeaderCN, nil, nil, []x509.ExtKeyUsage{x509.ExtKeyUsageClientAuth}, runtime.RequestHeaderCA, runtime.RequestHeaderCAKey, runtime.ClientAuthProxyCert, runtime.ClientAuthProxyKey); err != nil { return err } return nil } type signedCertFactory = func(commonName string, organization []string, certFile, keyFile string) (bool, error) func createServerSigningCertKey(config *config.Control) (bool, error) { runtime := config.Runtime TokenCA := filepath.Join(config.DataDir, "tls", "token-ca.crt") TokenCAKey := filepath.Join(config.DataDir, "tls", "token-ca.key") if exists(TokenCA, TokenCAKey) && !exists(runtime.ServerCA) && !exists(runtime.ServerCAKey) { logrus.Infof("Upgrading token-ca files to server-ca") if err := os.Link(TokenCA, runtime.ServerCA); err != nil { return false, err } if err := os.Link(TokenCAKey, runtime.ServerCAKey); err != nil { return false, err } return true, nil } return createSigningCertKey(version.Program+"-server", runtime.ServerCA, runtime.ServerCAKey) } func addSANs(altNames *certutil.AltNames, sans []string) { for _, san := range sans { ip := net.ParseIP(san) if ip == nil { altNames.DNSNames = append(altNames.DNSNames, san) } else { altNames.IPs = append(altNames.IPs, ip) } } } func fieldsChanged(certFile string, commonName string, organization []string, sans *certutil.AltNames, caCertFile string) bool { if sans == nil { sans = &certutil.AltNames{} } certificates, err := certutil.CertsFromFile(certFile) if err != nil || len(certificates) == 0 { return false } if certificates[0].Subject.CommonName != commonName { return true } if !sets.NewString(certificates[0].Subject.Organization...).Equal(sets.NewString(organization...)) { return true } if !sets.NewString(certificates[0].DNSNames...).HasAll(sans.DNSNames...) { return true } ips := sets.NewString() for _, ip := range certificates[0].IPAddresses { ips.Insert(ip.String()) } for _, ip := range sans.IPs { if !ips.Has(ip.String()) { return true } } caCertificates, err := certutil.CertsFromFile(caCertFile) if err != nil || len(caCertificates) == 0 { return false } verifyOpts := x509.VerifyOptions{ Roots: x509.NewCertPool(), KeyUsages: []x509.ExtKeyUsage{ x509.ExtKeyUsageAny, }, } for _, cert := range caCertificates { verifyOpts.Roots.AddCert(cert) } if _, err := certificates[0].Verify(verifyOpts); err != nil { return true } return false } func createClientCertKey(regen bool, commonName string, organization []string, altNames *certutil.AltNames, extKeyUsage []x509.ExtKeyUsage, caCertFile, caKeyFile, certFile, keyFile string) (bool, error) { // check for reasons to renew the certificate even if not manually requested. regen = regen || expired(certFile) || fieldsChanged(certFile, commonName, organization, altNames, caCertFile) if !regen { if exists(certFile, keyFile) { return false, nil } } caKey, err := certutil.PrivateKeyFromFile(caKeyFile) if err != nil { return false, err } caCert, err := certutil.CertsFromFile(caCertFile) if err != nil { return false, err } keyBytes, _, err := certutil.LoadOrGenerateKeyFile(keyFile, regen) if err != nil { return false, err } key, err := certutil.ParsePrivateKeyPEM(keyBytes) if err != nil { return false, err } cfg := certutil.Config{ CommonName: commonName, Organization: organization, Usages: extKeyUsage, } if altNames != nil { cfg.AltNames = *altNames } cert, err := certutil.NewSignedCert(cfg, key.(crypto.Signer), caCert[0], caKey.(crypto.Signer)) if err != nil { return false, err } return true, certutil.WriteCert(certFile, append(certutil.EncodeCertPEM(cert), certutil.EncodeCertPEM(caCert[0])...)) } func exists(files ...string) bool { for _, file := range files { if _, err := os.Stat(file); err != nil { return false } } return true } func genServiceAccount(runtime *config.ControlRuntime) error { _, keyErr := os.Stat(runtime.ServiceKey) if keyErr == nil { return nil } key, err := certutil.NewPrivateKey() if err != nil { return err } return certutil.WriteKey(runtime.ServiceKey, certutil.EncodePrivateKeyPEM(key)) } func createSigningCertKey(prefix, certFile, keyFile string) (bool, error) { if exists(certFile, keyFile) { return false, nil } caKeyBytes, _, err := certutil.LoadOrGenerateKeyFile(keyFile, false) if err != nil { return false, err } caKey, err := certutil.ParsePrivateKeyPEM(caKeyBytes) if err != nil { return false, err } cfg := certutil.Config{ CommonName: fmt.Sprintf("%s-ca@%d", prefix, time.Now().Unix()), } cert, err := certutil.NewSelfSignedCACert(cfg, caKey.(crypto.Signer)) if err != nil { return false, err } if err := certutil.WriteCert(certFile, certutil.EncodeCertPEM(cert)); err != nil { return false, err } return true, nil } func expired(certFile string) bool { certificates, err := certutil.CertsFromFile(certFile) if err != nil { return false } return certutil.IsCertExpired(certificates[0], config.CertificateRenewDays) } func genEncryptionConfigAndState(controlConfig *config.Control) error { runtime := controlConfig.Runtime if !controlConfig.EncryptSecrets { return nil } if s, err := os.Stat(runtime.EncryptionConfig); err == nil && s.Size() > 0 { // On upgrade from older versions, the encryption hash may not exist, create it if _, err := os.Stat(runtime.EncryptionHash); errors.Is(err, os.ErrNotExist) { curEncryptionByte, err := ioutil.ReadFile(runtime.EncryptionConfig) if err != nil { return err } encryptionConfigHash := sha256.Sum256(curEncryptionByte) ann := "start-" + hex.EncodeToString(encryptionConfigHash[:]) return ioutil.WriteFile(controlConfig.Runtime.EncryptionHash, []byte(ann), 0600) } return nil } aescbcKey := make([]byte, aescbcKeySize, aescbcKeySize) _, err := cryptorand.Read(aescbcKey) if err != nil { return err } encodedKey := b64.StdEncoding.EncodeToString(aescbcKey) encConfig := apiserverconfigv1.EncryptionConfiguration{ TypeMeta: metav1.TypeMeta{ Kind: "EncryptionConfiguration", APIVersion: "apiserver.config.k8s.io/v1", }, Resources: []apiserverconfigv1.ResourceConfiguration{ { Resources: []string{"secrets"}, Providers: []apiserverconfigv1.ProviderConfiguration{ { AESCBC: &apiserverconfigv1.AESConfiguration{ Keys: []apiserverconfigv1.Key{ { Name: "aescbckey", Secret: encodedKey, }, }, }, }, { Identity: &apiserverconfigv1.IdentityConfiguration{}, }, }, }, }, } b, err := json.Marshal(encConfig) if err != nil { return err } if err := ioutil.WriteFile(runtime.EncryptionConfig, b, 0600); err != nil { return err } encryptionConfigHash := sha256.Sum256(b) ann := "start-" + hex.EncodeToString(encryptionConfigHash[:]) return ioutil.WriteFile(controlConfig.Runtime.EncryptionHash, []byte(ann), 0600) }