| 1 | package main |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "encoding/json" |
| 6 | "fmt" |
| 7 | "log" |
| 8 | "slices" |
| 9 | "strings" |
| 10 | |
| 11 | "reasonix/internal/remote/bootstrap" |
| 12 | ) |
| 13 | |
| 14 | // serveCapabilityBrowser is the token a serve advertises on its token |
| 15 | // handshake when it was started with a browser broker (and accepts |
| 16 | // POST /browser/broker rebinds). Older serves omit the header entirely. |
| 17 | const serveCapabilityBrowser = "browser" |
| 18 | |
| 19 | // browserBrokerCallback is the bootstrap BrowserBroker hook for one ensure |
| 20 | // round: it mints this connection generation's token and opens the reverse |
| 21 | // tunnel only when the desktop shell can host browser surfaces. A desktop |
| 22 | // without host mode returns nil, launching the serve without a broker. |
| 23 | func (m *desktopRemoteManager) browserBrokerCallback(c desktopSSHClient, hostID string, gen *managedHost) func(context.Context) (*bootstrap.BrowserBrokerOptions, error) { |
| 24 | return func(ctx context.Context) (*bootstrap.BrowserBrokerOptions, error) { |
| 25 | app, ok := m.sink.(*App) |
| 26 | if !ok || app == nil || !app.hostMode() { |
| 27 | return nil, nil |
| 28 | } |
| 29 | if !m.isCurrent(hostID, gen) { |
| 30 | return nil, fmt.Errorf("browser broker: host %q connection was replaced", hostID) |
| 31 | } |
| 32 | token, port, err := app.registerBrowserBrokerRoute(hostID, gen) |
| 33 | if err != nil { |
| 34 | return nil, err |
| 35 | } |
| 36 | remotePort, err := ensureBrowserBrokerForward(c, hostID, port) |
| 37 | if err != nil { |
| 38 | app.revokeBrowserBrokerRoutes(hostID) |
| 39 | return nil, fmt.Errorf("browser broker: reverse tunnel: %w", err) |
| 40 | } |
| 41 | return &bootstrap.BrowserBrokerOptions{ |
| 42 | BaseURL: fmt.Sprintf("http://127.0.0.1:%d", remotePort), |
| 43 | Token: token, |
| 44 | }, nil |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | // rebindBrowserBroker re-points a REUSED serve at the new connection |
| 49 | // generation's broker: the process environment still carries the dead |
| 50 | // generation's endpoint and token, so the desktop rotates the route and posts |
| 51 | // the fresh pair. Serves without the browser capability keep every existing |
| 52 | // feature untouched. |
| 53 | func (m *desktopRemoteManager) rebindBrowserBroker(ctx context.Context, c desktopSSHClient, mh *managedHost, hostID string, view RemoteServerView, token string) error { |
| 54 | app, ok := m.sink.(*App) |
| 55 | if !ok || app == nil || !app.hostMode() { |
| 56 | return nil |
| 57 | } |
| 58 | if strings.TrimSpace(view.LocalURL) == "" || token == "" { |
| 59 | return nil |
| 60 | } |
| 61 | if !m.isCurrent(hostID, mh) { |
| 62 | return fmt.Errorf("browser broker: host %q connection was replaced", hostID) |
| 63 | } |
| 64 | client, err := newServeHTTPClient(view.LocalURL) |
| 65 | if err != nil { |
| 66 | return err |
| 67 | } |
| 68 | caps, err := serveHandshakeCapabilities(ctx, client, view.LocalURL, token) |
| 69 | if err != nil { |
| 70 | return fmt.Errorf("browser broker: handshake: %w", err) |
| 71 | } |
| 72 | if !slices.Contains(caps, serveCapabilityBrowser) { |
| 73 | return nil |
| 74 | } |
| 75 | brokerToken, port, err := app.registerBrowserBrokerRoute(hostID, mh) |
| 76 | if err != nil { |
| 77 | return err |
| 78 | } |
| 79 | remotePort, err := ensureBrowserBrokerForward(c, hostID, port) |
| 80 | if err != nil { |
| 81 | return fmt.Errorf("browser broker: reverse tunnel: %w", err) |
| 82 | } |
| 83 | body, err := json.Marshal(map[string]string{ |
| 84 | "endpoint": fmt.Sprintf("http://127.0.0.1:%d", remotePort), |
| 85 | "token": brokerToken, |
| 86 | }) |
| 87 | if err != nil { |
| 88 | return err |
| 89 | } |
| 90 | if err := servePost(ctx, client, serveURL(view.LocalURL, "/browser/broker"), body); err != nil { |
| 91 | return fmt.Errorf("browser broker: rebind: %w", err) |
| 92 | } |
| 93 | log.Printf("[remote] browser broker rebound host=%s url=%s", hostID, view.LocalURL) |
| 94 | return nil |
| 95 | } |
| 96 | |
| 97 | // rebindBrowserBrokerBestEffort runs the rebind without failing the ensure |
| 98 | // round: browser access is additive, and a serve whose rebind failed reports |
| 99 | // itself unavailable through the broker health check instead. |
| 100 | func (m *desktopRemoteManager) rebindBrowserBrokerBestEffort(ctx context.Context, c desktopSSHClient, mh *managedHost, hostID string, view RemoteServerView, token string) { |
| 101 | if err := m.rebindBrowserBroker(ctx, c, mh, hostID, view, token); err != nil { |
| 102 | log.Printf("[remote] browser broker rebind FAILED host=%s err=%v", hostID, err) |
| 103 | } |
| 104 | } |
| 105 | |
| 106 | // revokeBrowserBroker drops the host's broker route and reverse tunnel when |
| 107 | // its serve is stopped or the connection goes away. |
| 108 | func (m *desktopRemoteManager) revokeBrowserBroker(hostID string) { |
| 109 | if app, ok := m.sink.(*App); ok && app != nil { |
| 110 | app.revokeBrowserBrokerRoutes(hostID) |
| 111 | } |
| 112 | } |
| 113 |