package ca import ( "crypto/tls" "crypto/x509" "log" "net/http" "reflect" "github.com/go-chi/chi" "github.com/pkg/errors" "github.com/smallstep/certificates/api" "github.com/smallstep/certificates/authority" "github.com/smallstep/certificates/db" "github.com/smallstep/certificates/logging" "github.com/smallstep/certificates/monitoring" "github.com/smallstep/certificates/server" ) type options struct { configFile string password []byte database db.AuthDB } func (o *options) apply(opts []Option) { for _, fn := range opts { fn(o) } } // Option is the type of options passed to the CA constructor. type Option func(o *options) // WithConfigFile sets the given name as the configuration file name in the CA // options. func WithConfigFile(name string) Option { return func(o *options) { o.configFile = name } } // WithPassword sets the given password as the configured password in the CA // options. func WithPassword(password []byte) Option { return func(o *options) { o.password = password } } // WithDatabase sets the given authority database to the CA options. func WithDatabase(db db.AuthDB) Option { return func(o *options) { o.database = db } } // CA is the type used to build the complete certificate authority. It builds // the HTTP server, set ups the middlewares and the HTTP handlers. type CA struct { auth *authority.Authority config *authority.Config srv *server.Server opts *options renewer *TLSRenewer } // New creates and initializes the CA with the given configuration and options. func New(config *authority.Config, opts ...Option) (*CA, error) { ca := &CA{ config: config, opts: new(options), } ca.opts.apply(opts) return ca.Init(config) } // Init initializes the CA with the given configuration. func (ca *CA) Init(config *authority.Config) (*CA, error) { if l := len(ca.opts.password); l > 0 { ca.config.Password = string(ca.opts.password) } var opts []authority.Option if ca.opts.database != nil { opts = append(opts, authority.WithDatabase(ca.opts.database)) } auth, err := authority.New(config, opts...) if err != nil { return nil, err } tlsConfig, err := ca.getTLSConfig(auth) if err != nil { return nil, err } // Using chi as the main router mux := chi.NewRouter() handler := http.Handler(mux) // Add api endpoints in / and /1.0 routerHandler := api.New(auth) routerHandler.Route(mux) mux.Route("/1.0", func(r chi.Router) { routerHandler.Route(r) }) // Add monitoring if configured if len(config.Monitoring) > 0 { m, err := monitoring.New(config.Monitoring) if err != nil { return nil, err } handler = m.Middleware(handler) } // Add logger if configured if len(config.Logger) > 0 { logger, err := logging.New("ca", config.Logger) if err != nil { return nil, err } handler = logger.Middleware(handler) } ca.auth = auth ca.srv = server.New(config.Address, handler, tlsConfig) return ca, nil } // Run starts the CA calling to the server ListenAndServe method. func (ca *CA) Run() error { return ca.srv.ListenAndServe() } // Stop stops the CA calling to the server Shutdown method. func (ca *CA) Stop() error { ca.renewer.Stop() if err := ca.auth.Shutdown(); err != nil { log.Printf("error stopping ca.Authority: %+v\n", err) } return ca.srv.Shutdown() } // Reload reloads the configuration of the CA and calls to the server Reload // method. func (ca *CA) Reload() error { config, err := authority.LoadConfiguration(ca.opts.configFile) if err != nil { return errors.Wrap(err, "error reloading ca configuration") } logContinue := func(reason string) { log.Println(reason) log.Println("Continuing to run with the original configuration.") log.Println("You can force a restart by sending a SIGTERM signal and then restarting the step-ca.") } // Do not allow reload if the database configuration has changed. if !reflect.DeepEqual(ca.config.DB, config.DB) { logContinue("Reload failed because the database configuration has changed.") return errors.New("error reloading ca: database configuration cannot change") } newCA, err := New(config, WithPassword(ca.opts.password), WithConfigFile(ca.opts.configFile), WithDatabase(ca.auth.GetDatabase()), ) if err != nil { logContinue("Reload failed because the CA with new configuration could not be initialized.") return errors.Wrap(err, "error reloading ca") } if err = ca.srv.Reload(newCA.srv); err != nil { logContinue("Reload failed because server could not be replaced.") return errors.Wrap(err, "error reloading server") } // 1. Stop previous renewer // 2. Replace ca properties // Do not replace ca.srv ca.renewer.Stop() ca.auth = newCA.auth ca.config = newCA.config ca.opts = newCA.opts ca.renewer = newCA.renewer return nil } // getTLSConfig returns a TLSConfig for the CA server with a self-renewing // server certificate. func (ca *CA) getTLSConfig(auth *authority.Authority) (*tls.Config, error) { // Create initial TLS certificate tlsCrt, err := auth.GetTLSCertificate() if err != nil { return nil, err } // Start tls renewer with the new certificate. // If a renewer was started, attempt to stop it before. if ca.renewer != nil { ca.renewer.Stop() } ca.renewer, err = NewTLSRenewer(tlsCrt, auth.GetTLSCertificate) if err != nil { return nil, err } ca.renewer.Run() var tlsConfig *tls.Config if ca.config.TLS != nil { tlsConfig = ca.config.TLS.TLSConfig() } else { tlsConfig = &tls.Config{ MinVersion: tls.VersionTLS12, } } certPool := x509.NewCertPool() for _, crt := range auth.GetRootCertificates() { certPool.AddCert(crt) } // GetCertificate will only be called if the client supplies SNI // information or if tlsConfig.Certificates is empty. // When client requests are made using an IP address (as opposed to a domain // name) the server does not receive any SNI and may fallback to using the // first entry in the Certificates attribute; by setting the attribute to // empty we are implicitly forcing GetCertificate to be the only mechanism // by which the server can find it's own leaf Certificate. tlsConfig.Certificates = []tls.Certificate{} tlsConfig.GetCertificate = ca.renewer.GetCertificateForCA // Add support for mutual tls to renew certificates tlsConfig.ClientAuth = tls.VerifyClientCertIfGiven tlsConfig.ClientCAs = certPool // Use server's most preferred ciphersuite tlsConfig.PreferServerCipherSuites = true return tlsConfig, nil }