package authorization import ( "net/http" "sync" "github.com/Sirupsen/logrus" "github.com/docker/docker/pkg/plugingetter" "golang.org/x/net/context" ) // Middleware uses a list of plugins to // handle authorization in the API requests. type Middleware struct { mu sync.Mutex plugins []Plugin } // NewMiddleware creates a new Middleware // with a slice of plugins names. func NewMiddleware(names []string, pg plugingetter.PluginGetter) *Middleware { SetPluginGetter(pg) return &Middleware{ plugins: newPlugins(names), } } func (m *Middleware) getAuthzPlugins() []Plugin { m.mu.Lock() defer m.mu.Unlock() return m.plugins } // SetPlugins sets the plugin used for authorization func (m *Middleware) SetPlugins(names []string) { m.mu.Lock() m.plugins = newPlugins(names) m.mu.Unlock() } // RemovePlugin removes a single plugin from this authz middleware chain func (m *Middleware) RemovePlugin(name string) { m.mu.Lock() defer m.mu.Unlock() plugins := m.plugins[:0] for _, authPlugin := range m.plugins { if authPlugin.Name() != name { plugins = append(plugins, authPlugin) } } m.plugins = plugins } // WrapHandler returns a new handler function wrapping the previous one in the request chain. func (m *Middleware) WrapHandler(handler func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error) func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error { return func(ctx context.Context, w http.ResponseWriter, r *http.Request, vars map[string]string) error { plugins := m.getAuthzPlugins() if len(plugins) == 0 { return handler(ctx, w, r, vars) } user := "" userAuthNMethod := "" // Default authorization using existing TLS connection credentials // FIXME: Non trivial authorization mechanisms (such as advanced certificate validations, kerberos support // and ldap) will be extracted using AuthN feature, which is tracked under: // https://github.com/docker/docker/pull/20883 if r.TLS != nil && len(r.TLS.PeerCertificates) > 0 { user = r.TLS.PeerCertificates[0].Subject.CommonName userAuthNMethod = "TLS" } authCtx := NewCtx(plugins, user, userAuthNMethod, r.Method, r.RequestURI) if err := authCtx.AuthZRequest(w, r); err != nil { logrus.Errorf("AuthZRequest for %s %s returned error: %s", r.Method, r.RequestURI, err) return err } rw := NewResponseModifier(w) var errD error if errD = handler(ctx, rw, r, vars); errD != nil { logrus.Errorf("Handler for %s %s returned error: %s", r.Method, r.RequestURI, errD) } // There's a chance that the authCtx.plugins was updated. One of the reasons // this can happen is when an authzplugin is disabled. plugins = m.getAuthzPlugins() if len(plugins) == 0 { logrus.Debug("There are no authz plugins in the chain") return nil } authCtx.plugins = plugins if err := authCtx.AuthZResponse(rw, r); errD == nil && err != nil { logrus.Errorf("AuthZResponse for %s %s returned error: %s", r.Method, r.RequestURI, err) return err } if errD != nil { return errD } return nil } }