| package main |
| |
| import ( |
| "crypto/rand" |
| "encoding/base64" |
| "fmt" |
| "html/template" |
| "net" |
| "net/http" |
| "net/url" |
| "os" |
| "os/exec" |
| "strings" |
| |
| "veyron.io/veyron/veyron/services/identity/googleoauth" |
| "veyron.io/veyron/veyron2/vlog" |
| ) |
| |
| func getMacaroonForBlessRPC(blessServerURL string, blessedChan <-chan string) (<-chan string, error) { |
| // Setup a HTTP server to recieve a blessing macaroon from the identity server. |
| // Steps: |
| // 1. Generate a state token to be included in the HTTP request |
| // (though, arguably, the random port assigment for the HTTP server is enough |
| // for XSRF protection) |
| // 2. Setup a HTTP server which will receive the final blessing macaroon from the id server. |
| // 3. Print out the link (to start the auth flow) for the user to click. |
| // 4. Return the macaroon and the rpc object name(where to make the MacaroonBlesser.Bless RPC call) |
| // in the "result" channel. |
| var stateBuf [32]byte |
| if _, err := rand.Read(stateBuf[:]); err != nil { |
| return nil, fmt.Errorf("failed to generate state token for OAuth: %v", err) |
| } |
| state := base64.URLEncoding.EncodeToString(stateBuf[:]) |
| |
| ln, err := net.Listen("tcp", "127.0.0.1:0") |
| if err != nil { |
| return nil, fmt.Errorf("failed to setup authorization code interception server: %v", err) |
| } |
| result := make(chan string) |
| |
| redirectURL := fmt.Sprintf("http://%s/macaroon", ln.Addr()) |
| http.HandleFunc("/macaroon", func(w http.ResponseWriter, r *http.Request) { |
| w.Header().Set("Content-Type", "text/html") |
| tmplArgs := struct { |
| Blessings, ErrShort, ErrLong string |
| }{} |
| defer func() { |
| if len(tmplArgs.ErrShort) > 0 { |
| w.WriteHeader(http.StatusBadRequest) |
| } |
| if err := tmpl.Execute(w, tmplArgs); err != nil { |
| vlog.Info("Failed to render template:", err) |
| } |
| }() |
| |
| toolState := r.FormValue("state") |
| if toolState != state { |
| tmplArgs.ErrShort = "Unexpected request" |
| tmplArgs.ErrLong = "Mismatched state parameter. Possible cross-site-request-forgery?" |
| return |
| } |
| result <- r.FormValue("macaroon") |
| result <- r.FormValue("object_name") |
| defer close(result) |
| blessed, ok := <-blessedChan |
| if !ok { |
| tmplArgs.ErrShort = "No blessings received" |
| tmplArgs.ErrLong = "Unable to obtain blessings from the Veyron service" |
| return |
| } |
| tmplArgs.Blessings = blessed |
| ln.Close() |
| }) |
| go http.Serve(ln, nil) |
| |
| // Print the link to start the flow. |
| url, err := seekBlessingsURL(blessServerURL, redirectURL, state) |
| if err != nil { |
| return nil, fmt.Errorf("failed to create seekBlessingsURL: %s", err) |
| } |
| fmt.Fprintln(os.Stderr, "Please visit the following URL to seek blessings:") |
| fmt.Fprintln(os.Stderr, url) |
| // Make an attempt to start the browser as a convenience. |
| // If it fails, doesn't matter - the client can see the URL printed above. |
| // Use exec.Command().Start instead of exec.Command().Run since there is no |
| // need to wait for the command to return (and indeed on some window managers, |
| // the command will not exit until the browser is closed). |
| if len(openCommand) != 0 { |
| exec.Command(openCommand, url).Start() |
| } |
| return result, nil |
| } |
| |
| func seekBlessingsURL(blessServerURL, redirectURL, state string) (string, error) { |
| baseURL, err := url.Parse(joinURL(blessServerURL, googleoauth.SeekBlessingsRoute)) |
| if err != nil { |
| return "", fmt.Errorf("failed to parse url: %v", err) |
| } |
| params := url.Values{} |
| params.Add("redirect_url", redirectURL) |
| params.Add("state", state) |
| baseURL.RawQuery = params.Encode() |
| return baseURL.String(), nil |
| } |
| |
| func joinURL(baseURL, suffix string) string { |
| if !strings.HasSuffix(baseURL, "/") { |
| baseURL += "/" |
| } |
| return baseURL + suffix |
| } |
| |
| var tmpl = template.Must(template.New("name").Parse(`<!doctype html> |
| <html> |
| <head> |
| <meta charset="UTF-8"> |
| <title>Veyron Identity: Google</title> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0"> |
| <link rel="stylesheet" href="//netdna.bootstrapcdn.com/bootstrap/3.2.0/css/bootstrap.min.css"> |
| {{if .Blessings}} |
| <!--Attempt to close the window. Though this script does not work on many browser configurations--> |
| <script type="text/javascript">window.close();</script> |
| {{end}} |
| </head> |
| <body> |
| <div class="container"> |
| {{if .ErrShort}} |
| <h1><span class="label label-danger">error</span>{{.ErrShort}}</h1> |
| <div class="well">{{.ErrLong}}</div> |
| {{else}} |
| <h3>Received blessings: <tt>{{.Blessings}}</tt></h3> |
| {{end}} |
| </div> |
| </body> |
| </html>`)) |
