package server import ( "context" "encoding/json" "errors" "fmt" "net/http" "net/url" "path" "strings" "sync" "sync/atomic" "time" "golang.org/x/crypto/bcrypt" "github.com/gorilla/handlers" "github.com/gorilla/mux" "github.com/sirupsen/logrus" "github.com/coreos/dex/connector" "github.com/coreos/dex/connector/authproxy" "github.com/coreos/dex/connector/github" "github.com/coreos/dex/connector/gitlab" "github.com/coreos/dex/connector/ldap" "github.com/coreos/dex/connector/mock" "github.com/coreos/dex/connector/oidc" "github.com/coreos/dex/connector/saml" "github.com/coreos/dex/storage" ) // LocalConnector is the local passwordDB connector which is an internal // connector maintained by the server. const LocalConnector = "local" // Connector is a connector with resource version metadata. type Connector struct { ResourceVersion string Connector connector.Connector } // Config holds the server's configuration options. // // Multiple servers using the same storage are expected to be configured identically. type Config struct { Issuer string // The backing persistence layer. Storage storage.Storage // Valid values are "code" to enable the code flow and "token" to enable the implicit // flow. If no response types are supplied this value defaults to "code". SupportedResponseTypes []string // List of allowed origins for CORS requests on discovery, token and keys endpoint. // If none are indicated, CORS requests are disabled. Passing in "*" will allow any // domain. AllowedOrigins []string // If enabled, the server won't prompt the user to approve authorization requests. // Logging in implies approval. SkipApprovalScreen bool RotateKeysAfter time.Duration // Defaults to 6 hours. IDTokensValidFor time.Duration // Defaults to 24 hours GCFrequency time.Duration // Defaults to 5 minutes // If specified, the server will use this function for determining time. Now func() time.Time Web WebConfig Logger logrus.FieldLogger } // WebConfig holds the server's frontend templates and asset configuration. // // These are currently very custom to CoreOS and it's not recommended that // outside users attempt to customize these. type WebConfig struct { // A filepath to web static. // // It is expected to contain the following directories: // // * static - Static static served at "( issuer URL )/static". // * templates - HTML templates controlled by dex. // * themes/(theme) - Static static served at "( issuer URL )/theme". // Dir string // Defaults to "( issuer URL )/theme/logo.png" LogoURL string // Defaults to "dex" Issuer string // Defaults to "coreos" Theme string } func value(val, defaultValue time.Duration) time.Duration { if val == 0 { return defaultValue } return val } // Server is the top level object. type Server struct { issuerURL url.URL // mutex for the connectors map. mu sync.Mutex // Map of connector IDs to connectors. connectors map[string]Connector storage storage.Storage mux http.Handler templates *templates // If enabled, don't prompt user for approval after logging in through connector. skipApproval bool supportedResponseTypes map[string]bool now func() time.Time idTokensValidFor time.Duration logger logrus.FieldLogger } // NewServer constructs a server from the provided config. func NewServer(ctx context.Context, c Config) (*Server, error) { return newServer(ctx, c, defaultRotationStrategy( value(c.RotateKeysAfter, 6*time.Hour), value(c.IDTokensValidFor, 24*time.Hour), )) } func newServer(ctx context.Context, c Config, rotationStrategy rotationStrategy) (*Server, error) { issuerURL, err := url.Parse(c.Issuer) if err != nil { return nil, fmt.Errorf("server: can't parse issuer URL") } if c.Storage == nil { return nil, errors.New("server: storage cannot be nil") } if len(c.SupportedResponseTypes) == 0 { c.SupportedResponseTypes = []string{responseTypeCode} } supported := make(map[string]bool) for _, respType := range c.SupportedResponseTypes { switch respType { case responseTypeCode, responseTypeIDToken, responseTypeToken: default: return nil, fmt.Errorf("unsupported response_type %q", respType) } supported[respType] = true } web := webConfig{ dir: c.Web.Dir, logoURL: c.Web.LogoURL, issuerURL: c.Issuer, issuer: c.Web.Issuer, theme: c.Web.Theme, } static, theme, tmpls, err := loadWebConfig(web) if err != nil { return nil, fmt.Errorf("server: failed to load web static: %v", err) } now := c.Now if now == nil { now = time.Now } s := &Server{ issuerURL: *issuerURL, connectors: make(map[string]Connector), storage: newKeyCacher(c.Storage, now), supportedResponseTypes: supported, idTokensValidFor: value(c.IDTokensValidFor, 24*time.Hour), skipApproval: c.SkipApprovalScreen, now: now, templates: tmpls, logger: c.Logger, } // Retrieves connector objects in backend storage. This list includes the static connectors // defined in the ConfigMap and dynamic connectors retrieved from the storage. storageConnectors, err := c.Storage.ListConnectors() if err != nil { return nil, fmt.Errorf("server: failed to list connector objects from storage: %v", err) } if len(storageConnectors) == 0 && len(s.connectors) == 0 { return nil, errors.New("server: no connectors specified") } for _, conn := range storageConnectors { if _, err := s.OpenConnector(conn); err != nil { return nil, fmt.Errorf("server: Failed to open connector %s: %v", conn.ID, err) } } r := mux.NewRouter() handleFunc := func(p string, h http.HandlerFunc) { r.HandleFunc(path.Join(issuerURL.Path, p), h) } handlePrefix := func(p string, h http.Handler) { prefix := path.Join(issuerURL.Path, p) r.PathPrefix(prefix).Handler(http.StripPrefix(prefix, h)) } handleWithCORS := func(p string, h http.HandlerFunc) { var handler http.Handler = h if len(c.AllowedOrigins) > 0 { corsOption := handlers.AllowedOrigins(c.AllowedOrigins) handler = handlers.CORS(corsOption)(handler) } r.Handle(path.Join(issuerURL.Path, p), handler) } r.NotFoundHandler = http.HandlerFunc(http.NotFound) discoveryHandler, err := s.discoveryHandler() if err != nil { return nil, err } handleWithCORS("/.well-known/openid-configuration", discoveryHandler) // TODO(ericchiang): rate limit certain paths based on IP. handleWithCORS("/token", s.handleToken) handleWithCORS("/keys", s.handlePublicKeys) handleFunc("/auth", s.handleAuthorization) handleFunc("/auth/{connector}", s.handleConnectorLogin) r.HandleFunc(path.Join(issuerURL.Path, "/callback"), func(w http.ResponseWriter, r *http.Request) { // Strip the X-Remote-* headers to prevent security issues on // misconfigured authproxy connector setups. for key := range r.Header { if strings.HasPrefix(strings.ToLower(key), "x-remote-") { r.Header.Del(key) } } s.handleConnectorCallback(w, r) }) // For easier connector-specific web server configuration, e.g. for the // "authproxy" connector. handleFunc("/callback/{connector}", s.handleConnectorCallback) handleFunc("/approval", s.handleApproval) handleFunc("/healthz", s.handleHealth) handlePrefix("/static", static) handlePrefix("/theme", theme) s.mux = r s.startKeyRotation(ctx, rotationStrategy, now) s.startGarbageCollection(ctx, value(c.GCFrequency, 5*time.Minute), now) return s, nil } func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) { s.mux.ServeHTTP(w, r) } func (s *Server) absPath(pathItems ...string) string { paths := make([]string, len(pathItems)+1) paths[0] = s.issuerURL.Path copy(paths[1:], pathItems) return path.Join(paths...) } func (s *Server) absURL(pathItems ...string) string { u := s.issuerURL u.Path = s.absPath(pathItems...) return u.String() } func newPasswordDB(s storage.Storage) interface { connector.Connector connector.PasswordConnector } { return passwordDB{s} } type passwordDB struct { s storage.Storage } func (db passwordDB) Login(ctx context.Context, s connector.Scopes, email, password string) (connector.Identity, bool, error) { p, err := db.s.GetPassword(email) if err != nil { if err != storage.ErrNotFound { return connector.Identity{}, false, fmt.Errorf("get password: %v", err) } return connector.Identity{}, false, nil } // This check prevents dex users from logging in using static passwords // configured with hash costs that are too high or low. if err := checkCost(p.Hash); err != nil { return connector.Identity{}, false, err } if err := bcrypt.CompareHashAndPassword(p.Hash, []byte(password)); err != nil { return connector.Identity{}, false, nil } return connector.Identity{ UserID: p.UserID, Username: p.Username, Email: p.Email, EmailVerified: true, }, true, nil } func (db passwordDB) Refresh(ctx context.Context, s connector.Scopes, identity connector.Identity) (connector.Identity, error) { // If the user has been deleted, the refresh token will be rejected. p, err := db.s.GetPassword(identity.Email) if err != nil { if err == storage.ErrNotFound { return connector.Identity{}, errors.New("user not found") } return connector.Identity{}, fmt.Errorf("get password: %v", err) } // User removed but a new user with the same email exists. if p.UserID != identity.UserID { return connector.Identity{}, errors.New("user not found") } // If a user has updated their username, that will be reflected in the // refreshed token. // // No other fields are expected to be refreshable as email is effectively used // as an ID and this implementation doesn't deal with groups. identity.Username = p.Username return identity, nil } // newKeyCacher returns a storage which caches keys so long as the next func newKeyCacher(s storage.Storage, now func() time.Time) storage.Storage { if now == nil { now = time.Now } return &keyCacher{Storage: s, now: now} } type keyCacher struct { storage.Storage now func() time.Time keys atomic.Value // Always holds nil or type *storage.Keys. } func (k *keyCacher) GetKeys() (storage.Keys, error) { keys, ok := k.keys.Load().(*storage.Keys) if ok && keys != nil && k.now().Before(keys.NextRotation) { return *keys, nil } storageKeys, err := k.Storage.GetKeys() if err != nil { return storageKeys, err } if k.now().Before(storageKeys.NextRotation) { k.keys.Store(&storageKeys) } return storageKeys, nil } func (s *Server) startGarbageCollection(ctx context.Context, frequency time.Duration, now func() time.Time) { go func() { for { select { case <-ctx.Done(): return case <-time.After(frequency): if r, err := s.storage.GarbageCollect(now()); err != nil { s.logger.Errorf("garbage collection failed: %v", err) } else if r.AuthRequests > 0 || r.AuthCodes > 0 { s.logger.Infof("garbage collection run, delete auth requests=%d, auth codes=%d", r.AuthRequests, r.AuthCodes) } } } }() return } // ConnectorConfig is a configuration that can open a connector. type ConnectorConfig interface { Open(id string, logger logrus.FieldLogger) (connector.Connector, error) } // ConnectorsConfig variable provides an easy way to return a config struct // depending on the connector type. var ConnectorsConfig = map[string]func() ConnectorConfig{ "mockCallback": func() ConnectorConfig { return new(mock.CallbackConfig) }, "mockPassword": func() ConnectorConfig { return new(mock.PasswordConfig) }, "ldap": func() ConnectorConfig { return new(ldap.Config) }, "github": func() ConnectorConfig { return new(github.Config) }, "gitlab": func() ConnectorConfig { return new(gitlab.Config) }, "oidc": func() ConnectorConfig { return new(oidc.Config) }, "saml": func() ConnectorConfig { return new(saml.Config) }, "authproxy": func() ConnectorConfig { return new(authproxy.Config) }, // Keep around for backwards compatibility. "samlExperimental": func() ConnectorConfig { return new(saml.Config) }, } // openConnector will parse the connector config and open the connector. func openConnector(logger logrus.FieldLogger, conn storage.Connector) (connector.Connector, error) { var c connector.Connector f, ok := ConnectorsConfig[conn.Type] if !ok { return c, fmt.Errorf("unknown connector type %q", conn.Type) } connConfig := f() if len(conn.Config) != 0 { data := []byte(string(conn.Config)) if err := json.Unmarshal(data, connConfig); err != nil { return c, fmt.Errorf("parse connector config: %v", err) } } c, err := connConfig.Open(conn.ID, logger) if err != nil { return c, fmt.Errorf("failed to create connector %s: %v", conn.ID, err) } return c, nil } // OpenConnector updates server connector map with specified connector object. func (s *Server) OpenConnector(conn storage.Connector) (Connector, error) { var c connector.Connector if conn.Type == LocalConnector { c = newPasswordDB(s.storage) } else { var err error c, err = openConnector(s.logger.WithField("connector", conn.Name), conn) if err != nil { return Connector{}, fmt.Errorf("failed to open connector: %v", err) } } connector := Connector{ ResourceVersion: conn.ResourceVersion, Connector: c, } s.mu.Lock() s.connectors[conn.ID] = connector s.mu.Unlock() return connector, nil } // getConnector retrieves the connector object with the given id from the storage // and updates the connector list for server if necessary. func (s *Server) getConnector(id string) (Connector, error) { storageConnector, err := s.storage.GetConnector(id) if err != nil { return Connector{}, fmt.Errorf("failed to get connector object from storage: %v", err) } var conn Connector var ok bool s.mu.Lock() conn, ok = s.connectors[id] s.mu.Unlock() if !ok || storageConnector.ResourceVersion != conn.ResourceVersion { // Connector object does not exist in server connectors map or // has been updated in the storage. Need to get latest. conn, err := s.OpenConnector(storageConnector) if err != nil { return Connector{}, fmt.Errorf("failed to open connector: %v", err) } return conn, nil } return conn, nil }