package token import ( "bytes" "encoding/base64" "fmt" "io" "net/http" "net/url" "os" "time" "github.com/pkg/errors" "github.com/rs/zerolog" ) const ( baseStoreURL = "https://login.cloudflareaccess.org/" clientTimeout = time.Second * 60 ) // RunTransfer does the transfer "dance" with the end result downloading the supported resource. // The expanded description is run is encapsulation of shared business logic needed // to request a resource (token/cert/etc) from the transfer service (loginhelper). // The "dance" we refer to is building a HTTP request, opening that in a browser waiting for // the user to complete an action, while it long polls in the background waiting for an // action to be completed to download the resource. func RunTransfer(transferURL *url.URL, resourceName, key, value string, shouldEncrypt bool, useHostOnly bool, log *zerolog.Logger) ([]byte, error) { encrypterClient, err := NewEncrypter("cloudflared_priv.pem", "cloudflared_pub.pem") if err != nil { return nil, err } requestURL, err := buildRequestURL(transferURL, key, value+encrypterClient.PublicKey(), shouldEncrypt, useHostOnly) if err != nil { return nil, err } // See AUTH-1423 for why we use stderr (the way git wraps ssh) err = OpenBrowser(requestURL) if err != nil { fmt.Fprintf(os.Stderr, "Please open the following URL and log in with your Cloudflare account:\n\n%s\n\nLeave cloudflared running to download the %s automatically.\n", requestURL, resourceName) } else { fmt.Fprintf(os.Stderr, "A browser window should have opened at the following URL:\n\n%s\n\nIf the browser failed to open, please visit the URL above directly in your browser.\n", requestURL) } var resourceData []byte if shouldEncrypt { buf, key, err := transferRequest(baseStoreURL+"transfer/"+encrypterClient.PublicKey(), log) if err != nil { return nil, err } decodedBuf, err := base64.StdEncoding.DecodeString(string(buf)) if err != nil { return nil, err } decrypted, err := encrypterClient.Decrypt(decodedBuf, key) if err != nil { return nil, err } resourceData = decrypted } else { buf, _, err := transferRequest(baseStoreURL+encrypterClient.PublicKey(), log) if err != nil { return nil, err } resourceData = buf } return resourceData, nil } // BuildRequestURL creates a request suitable for a resource transfer. // it will return a constructed url based off the base url and query key/value provided. // cli will build a url for cli transfer request. func buildRequestURL(baseURL *url.URL, key, value string, cli, useHostOnly bool) (string, error) { q := baseURL.Query() q.Set(key, value) baseURL.RawQuery = q.Encode() if useHostOnly { baseURL.Path = "" } // TODO: pass arg for tunnel login if !cli { return baseURL.String(), nil } q.Set("redirect_url", baseURL.String()) // we add the token as a query param on both the redirect_url and the main url q.Set("send_org_token", "true") // indicates that the cli endpoint should return both the org and app token q.Set("edge_token_transfer", "true") // use new LoginHelper service built on workers baseURL.RawQuery = q.Encode() // and this actual baseURL. baseURL.Path = "cdn-cgi/access/cli" return baseURL.String(), nil } // transferRequest downloads the requested resource from the request URL func transferRequest(requestURL string, log *zerolog.Logger) ([]byte, string, error) { client := &http.Client{Timeout: clientTimeout} const pollAttempts = 10 // we do "long polling" on the endpoint to get the resource. for i := 0; i < pollAttempts; i++ { buf, key, err := poll(client, requestURL, log) if err != nil { return nil, "", err } else if len(buf) > 0 { return buf, key, nil } } return nil, "", errors.New("Failed to fetch resource") } // poll the endpoint for the request resource, waiting for the user interaction func poll(client *http.Client, requestURL string, log *zerolog.Logger) ([]byte, string, error) { req, err := http.NewRequest(http.MethodGet, requestURL, nil) if err != nil { return nil, "", err } req.Header.Set("User-Agent", userAgent) resp, err := client.Do(req) if err != nil { return nil, "", err } defer resp.Body.Close() // ignore everything other than server errors as the resource // may not exist until the user does the interaction if resp.StatusCode >= 500 { return nil, "", fmt.Errorf("error on request %d", resp.StatusCode) } if resp.StatusCode != 200 { log.Info().Msg("Waiting for login...") return nil, "", nil } buf := new(bytes.Buffer) if _, err := io.Copy(buf, resp.Body); err != nil { return nil, "", err } return buf.Bytes(), resp.Header.Get("service-public-key"), nil }