TUN-7134: Acquire token for cloudflared tail

cloudflared tail will now fetch the management token from by making
a request to the Cloudflare API using the cert.pem (acquired from
cloudflared login).

Refactored some of the credentials code into it's own package as
to allow for easier use between subcommands outside of
`cloudflared tunnel`.

cmd/cloudflared/cliutil/build_info.go

@@ -47,3 +47,7 @@ func (bi *BuildInfo) GetBuildTypeMsg() string {
 	}
 	return fmt.Sprintf(" with %s", bi.BuildType)
 }
+
+func (bi *BuildInfo) UserAgent() string {
+	return fmt.Sprintf("cloudflared/%s", bi.CloudflaredVersion)
+}

cmd/cloudflared/main.go

@@ -90,7 +90,7 @@ func main() {
 	updater.Init(Version)
 	tracing.Init(Version)
 	token.Init(Version)
-	tail.Init(Version)
+	tail.Init(bInfo)
 	runApp(app, graceShutdownC)
 }
 

cmd/cloudflared/tail/cmd.go

@@ -2,6 +2,7 @@ package tail
 
 import (
 	"encoding/json"
+	"errors"
 	"fmt"
 	"net/http"
 	"net/url"
@@ -10,28 +11,32 @@ import (
 	"syscall"
 	"time"
 
+	"github.com/google/uuid"
 	"github.com/mattn/go-colorable"
 	"github.com/rs/zerolog"
 	"github.com/urfave/cli/v2"
 	"nhooyr.io/websocket"
 
+	"github.com/cloudflare/cloudflared/cmd/cloudflared/cliutil"
+	"github.com/cloudflare/cloudflared/credentials"
 	"github.com/cloudflare/cloudflared/logger"
 	"github.com/cloudflare/cloudflared/management"
 )
 
 var (
-	version string
+	buildInfo *cliutil.BuildInfo
 )
 
-func Init(v string) {
-	version = v
+func Init(bi *cliutil.BuildInfo) {
+	buildInfo = bi
 }
 
 func Command() *cli.Command {
 	return &cli.Command{
-		Name:   "tail",
-		Action: Run,
-		Usage:  "Stream logs from a remote cloudflared",
+		Name:      "tail",
+		Action:    Run,
+		Usage:     "Stream logs from a remote cloudflared",
+		UsageText: "cloudflared tail [tail command options] [TUNNEL-ID]",
 		Flags: []cli.Flag{
 			&cli.StringFlag{
 				Name:    "connector-id",
@@ -75,6 +80,12 @@ func Command() *cli.Command {
 				Usage:   "Application logging level {debug, info, warn, error, fatal}",
 				EnvVars: []string{"TUNNEL_LOGLEVEL"},
 			},
+			&cli.StringFlag{
+				Name:    credentials.OriginCertFlag,
+				Usage:   "Path to the certificate generated for your origin when you run cloudflared login.",
+				EnvVars: []string{"TUNNEL_ORIGIN_CERT"},
+				Value:   credentials.FindDefaultOriginCertPath(),
+			},
 		},
 	}
 }
@@ -159,6 +170,59 @@ func parseFilters(c *cli.Context) (*management.StreamingFilters, error) {
 	}, nil
 }
 
+// getManagementToken will make a call to the Cloudflare API to acquire a management token for the requested tunnel.
+func getManagementToken(c *cli.Context, log *zerolog.Logger) (string, error) {
+	userCreds, err := credentials.Read(c.String(credentials.OriginCertFlag), log)
+	if err != nil {
+		return "", err
+	}
+
+	client, err := userCreds.Client(c.String("api-url"), buildInfo.UserAgent(), log)
+	if err != nil {
+		return "", err
+	}
+
+	tunnelIDString := c.Args().First()
+	if tunnelIDString == "" {
+		return "", errors.New("no tunnel ID provided")
+	}
+	tunnelID, err := uuid.Parse(tunnelIDString)
+	if err != nil {
+		return "", errors.New("unable to parse provided tunnel id as a valid UUID")
+	}
+
+	token, err := client.GetManagementToken(tunnelID)
+	if err != nil {
+		return "", err
+	}
+
+	return token, nil
+}
+
+// buildURL will build the management url to contain the required query parameters to authenticate the request.
+func buildURL(c *cli.Context, log *zerolog.Logger) (url.URL, error) {
+	var err error
+	managementHostname := c.String("management-hostname")
+	token := c.String("token")
+	if token == "" {
+		token, err = getManagementToken(c, log)
+		if err != nil {
+			return url.URL{}, fmt.Errorf("unable to acquire management token for requested tunnel id: %w", err)
+		}
+	}
+	query := url.Values{}
+	query.Add("access_token", token)
+	connector := c.String("connector-id")
+	if connector != "" {
+		connectorID, err := uuid.Parse(connector)
+		if err != nil {
+			return url.URL{}, fmt.Errorf("unabled to parse 'connector-id' flag into a valid UUID: %w", err)
+		}
+		query.Add("connector_id", connectorID.String())
+	}
+	return url.URL{Scheme: "wss", Host: managementHostname, Path: "/logs", RawQuery: query.Encode()}, nil
+}
+
 // Run implements a foreground runner
 func Run(c *cli.Context) error {
 	log := createLogger(c)
@@ -173,12 +237,14 @@ func Run(c *cli.Context) error {
 		return nil
 	}
 
-	managementHostname := c.String("management-hostname")
-	token := c.String("token")
-	u := url.URL{Scheme: "wss", Host: managementHostname, Path: "/logs", RawQuery: "access_token=" + token}
+	u, err := buildURL(c, log)
+	if err != nil {
+		log.Err(err).Msg("unable to construct management request URL")
+		return nil
+	}
 
 	header := make(http.Header)
-	header.Add("User-Agent", "cloudflared/"+version)
+	header.Add("User-Agent", buildInfo.UserAgent())
 	trace := c.String("trace")
 	if trace != "" {
 		header["cf-trace-id"] = []string{trace}
@@ -206,6 +272,11 @@ func Run(c *cli.Context) error {
 		log.Error().Err(err).Msg("unable to request logs from management tunnel")
 		return nil
 	}
+	log.Debug().
+		Str("tunnel-id", c.Args().First()).
+		Str("connector-id", c.String("connector-id")).
+		Interface("filters", filters).
+		Msg("connected")
 
 	readerDone := make(chan struct{})
 

cmd/cloudflared/tunnel/cmd.go

@@ -28,6 +28,7 @@ import (
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/updater"
 	"github.com/cloudflare/cloudflared/config"
 	"github.com/cloudflare/cloudflared/connection"
+	"github.com/cloudflare/cloudflared/credentials"
 	"github.com/cloudflare/cloudflared/features"
 	"github.com/cloudflare/cloudflared/ingress"
 	"github.com/cloudflare/cloudflared/logger"
@@ -751,10 +752,10 @@ func configureCloudflaredFlags(shouldHide bool) []cli.Flag {
 			Hidden: shouldHide,
 		},
 		altsrc.NewStringFlag(&cli.StringFlag{
-			Name:    "origincert",
+			Name:    credentials.OriginCertFlag,
 			Usage:   "Path to the certificate generated for your origin when you run cloudflared login.",
 			EnvVars: []string{"TUNNEL_ORIGIN_CERT"},
-			Value:   findDefaultOriginCertPath(),
+			Value:   credentials.FindDefaultOriginCertPath(),
 			Hidden:  shouldHide,
 		}),
 		altsrc.NewDurationFlag(&cli.DurationFlag{

cmd/cloudflared/tunnel/configuration.go

@@ -3,17 +3,14 @@ package tunnel
 import (
 	"crypto/tls"
 	"fmt"
-	"io/ioutil"
 	mathRand "math/rand"
 	"net"
 	"net/netip"
 	"os"
-	"path/filepath"
 	"strings"
 	"time"
 
 	"github.com/google/uuid"
-	homedir "github.com/mitchellh/go-homedir"
 	"github.com/pkg/errors"
 	"github.com/rs/zerolog"
 	"github.com/urfave/cli/v2"
@@ -33,7 +30,6 @@ import (
 	tunnelpogs "github.com/cloudflare/cloudflared/tunnelrpc/pogs"
 )
 
-const LogFieldOriginCertPath = "originCertPath"
 const secretValue = "*****"
 
 var (
@@ -46,18 +42,6 @@ var (
 	configFlags = []string{"autoupdate-freq", "no-autoupdate", "retries", "protocol", "loglevel", "transport-loglevel", "origincert", "metrics", "metrics-update-freq", "edge-ip-version", "edge-bind-address"}
 )
 
-// returns the first path that contains a cert.pem file. If none of the DefaultConfigSearchDirectories
-// contains a cert.pem file, return empty string
-func findDefaultOriginCertPath() string {
-	for _, defaultConfigDir := range config.DefaultConfigSearchDirectories() {
-		originCertPath, _ := homedir.Expand(filepath.Join(defaultConfigDir, config.DefaultCredentialFile))
-		if ok, _ := config.FileExists(originCertPath); ok {
-			return originCertPath
-		}
-	}
-	return ""
-}
-
 func generateRandomClientID(log *zerolog.Logger) (string, error) {
 	u, err := uuid.NewRandom()
 	if err != nil {
@@ -128,62 +112,6 @@ func dnsProxyStandAlone(c *cli.Context, namedTunnel *connection.NamedTunnelPrope
 			namedTunnel != nil) // named tunnel
 }
 
-func findOriginCert(originCertPath string, log *zerolog.Logger) (string, error) {
-	if originCertPath == "" {
-		log.Info().Msgf("Cannot determine default origin certificate path. No file %s in %v", config.DefaultCredentialFile, config.DefaultConfigSearchDirectories())
-		if isRunningFromTerminal() {
-			log.Error().Msgf("You need to specify the origin certificate path with --origincert option, or set TUNNEL_ORIGIN_CERT environment variable. See %s for more information.", argumentsUrl)
-			return "", fmt.Errorf("client didn't specify origincert path when running from terminal")
-		} else {
-			log.Error().Msgf("You need to specify the origin certificate path by specifying the origincert option in the configuration file, or set TUNNEL_ORIGIN_CERT environment variable. See %s for more information.", serviceUrl)
-			return "", fmt.Errorf("client didn't specify origincert path")
-		}
-	}
-	var err error
-	originCertPath, err = homedir.Expand(originCertPath)
-	if err != nil {
-		log.Err(err).Msgf("Cannot resolve origin certificate path")
-		return "", fmt.Errorf("cannot resolve path %s", originCertPath)
-	}
-	// Check that the user has acquired a certificate using the login command
-	ok, err := config.FileExists(originCertPath)
-	if err != nil {
-		log.Error().Err(err).Msgf("Cannot check if origin cert exists at path %s", originCertPath)
-		return "", fmt.Errorf("cannot check if origin cert exists at path %s", originCertPath)
-	}
-	if !ok {
-		log.Error().Msgf(`Cannot find a valid certificate for your origin at the path:
-
-    %s
-
-If the path above is wrong, specify the path with the -origincert option.
-If you don't have a certificate signed by Cloudflare, run the command:
-
-	%s login
-`, originCertPath, os.Args[0])
-		return "", fmt.Errorf("cannot find a valid certificate at the path %s", originCertPath)
-	}
-
-	return originCertPath, nil
-}
-
-func readOriginCert(originCertPath string) ([]byte, error) {
-	// Easier to send the certificate as []byte via RPC than decoding it at this point
-	originCert, err := ioutil.ReadFile(originCertPath)
-	if err != nil {
-		return nil, fmt.Errorf("cannot read %s to load origin certificate", originCertPath)
-	}
-	return originCert, nil
-}
-
-func getOriginCert(originCertPath string, log *zerolog.Logger) ([]byte, error) {
-	if originCertPath, err := findOriginCert(originCertPath, log); err != nil {
-		return nil, err
-	} else {
-		return readOriginCert(originCertPath)
-	}
-}
-
 func prepareTunnelConfig(
 	c *cli.Context,
 	info *cliutil.BuildInfo,

cmd/cloudflared/tunnel/credential_finder.go

@@ -5,6 +5,7 @@ import (
 	"path/filepath"
 
 	"github.com/cloudflare/cloudflared/config"
+	"github.com/cloudflare/cloudflared/credentials"
 
 	"github.com/google/uuid"
 	"github.com/rs/zerolog"
@@ -56,13 +57,13 @@ func newSearchByID(id uuid.UUID, c *cli.Context, log *zerolog.Logger, fs fileSys
 }
 
 func (s searchByID) Path() (string, error) {
-	originCertPath := s.c.String("origincert")
+	originCertPath := s.c.String(credentials.OriginCertFlag)
 	originCertLog := s.log.With().
-		Str(LogFieldOriginCertPath, originCertPath).
+		Str("originCertPath", originCertPath).
 		Logger()
 
 	// Fallback to look for tunnel credentials in the origin cert directory
-	if originCertPath, err := findOriginCert(originCertPath, &originCertLog); err == nil {
+	if originCertPath, err := credentials.FindOriginCert(originCertPath, &originCertLog); err == nil {
 		originCertDir := filepath.Dir(originCertPath)
 		if filePath, err := tunnelFilePath(s.id, originCertDir); err == nil {
 			if s.fs.validFilePath(filePath) {

cmd/cloudflared/tunnel/login.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/cliutil"
 	"github.com/cloudflare/cloudflared/config"
+	"github.com/cloudflare/cloudflared/credentials"
 	"github.com/cloudflare/cloudflared/logger"
 	"github.com/cloudflare/cloudflared/token"
 )
@@ -85,7 +86,7 @@ func checkForExistingCert() (string, bool, error) {
 	if err != nil {
 		return "", false, err
 	}
-	path := filepath.Join(configPath, config.DefaultCredentialFile)
+	path := filepath.Join(configPath, credentials.DefaultCredentialFile)
 	fileInfo, err := os.Stat(path)
 	if err == nil && fileInfo.Size() > 0 {
 		return path, true, nil

cmd/cloudflared/tunnel/subcommand_context.go

@@ -13,9 +13,9 @@ import (
 	"github.com/rs/zerolog"
 	"github.com/urfave/cli/v2"
 
-	"github.com/cloudflare/cloudflared/certutil"
 	"github.com/cloudflare/cloudflared/cfapi"
 	"github.com/cloudflare/cloudflared/connection"
+	"github.com/cloudflare/cloudflared/credentials"
 	"github.com/cloudflare/cloudflared/logger"
 )
 
@@ -37,7 +37,7 @@ type subcommandContext struct {
 
 	// These fields should be accessed using their respective Getter
 	tunnelstoreClient cfapi.Client
-	userCredential    *userCredential
+	userCredential    *credentials.User
 }
 
 func newSubcommandContext(c *cli.Context) (*subcommandContext, error) {
@@ -56,65 +56,28 @@ func (sc *subcommandContext) credentialFinder(tunnelID uuid.UUID) CredFinder {
 	return newSearchByID(tunnelID, sc.c, sc.log, sc.fs)
 }
 
-type userCredential struct {
-	cert     *certutil.OriginCert
-	certPath string
-}
-
 func (sc *subcommandContext) client() (cfapi.Client, error) {
 	if sc.tunnelstoreClient != nil {
 		return sc.tunnelstoreClient, nil
 	}
-	credential, err := sc.credential()
+	cred, err := sc.credential()
 	if err != nil {
 		return nil, err
 	}
-	userAgent := fmt.Sprintf("cloudflared/%s", buildInfo.Version())
-	client, err := cfapi.NewRESTClient(
-		sc.c.String("api-url"),
-		credential.cert.AccountID,
-		credential.cert.ZoneID,
-		credential.cert.APIToken,
-		userAgent,
-		sc.log,
-	)
-
+	sc.tunnelstoreClient, err = cred.Client(sc.c.String("api-url"), buildInfo.UserAgent(), sc.log)
 	if err != nil {
 		return nil, err
 	}
-	sc.tunnelstoreClient = client
-	return client, nil
+	return sc.tunnelstoreClient, nil
 }
 
-func (sc *subcommandContext) credential() (*userCredential, error) {
+func (sc *subcommandContext) credential() (*credentials.User, error) {
 	if sc.userCredential == nil {
-		originCertPath := sc.c.String("origincert")
-		originCertLog := sc.log.With().
-			Str(LogFieldOriginCertPath, originCertPath).
-			Logger()
-
-		originCertPath, err := findOriginCert(originCertPath, &originCertLog)
+		uc, err := credentials.Read(sc.c.String(credentials.OriginCertFlag), sc.log)
 		if err != nil {
-			return nil, errors.Wrap(err, "Error locating origin cert")
-		}
-		blocks, err := readOriginCert(originCertPath)
-		if err != nil {
-			return nil, errors.Wrapf(err, "Can't read origin cert from %s", originCertPath)
-		}
-
-		cert, err := certutil.DecodeOriginCert(blocks)
-		if err != nil {
-			return nil, errors.Wrap(err, "Error decoding origin cert")
-		}
-
-		if cert.AccountID == "" {
-			return nil, errors.Errorf(`Origin certificate needs to be refreshed before creating new tunnels.\nDelete %s and run "cloudflared login" to obtain a new cert.`, originCertPath)
-		}
-
-		sc.userCredential = &userCredential{
-			cert:     cert,
-			certPath: originCertPath,
+			return nil, err
 		}
+		sc.userCredential = uc
 	}
 	return sc.userCredential, nil
 }
@@ -175,13 +138,13 @@ func (sc *subcommandContext) create(name string, credentialsFilePath string, sec
 		return nil, err
 	}
 	tunnelCredentials := connection.Credentials{
-		AccountTag:   credential.cert.AccountID,
+		AccountTag:   credential.AccountID(),
 		TunnelSecret: tunnelSecret,
 		TunnelID:     tunnel.ID,
 	}
 	usedCertPath := false
 	if credentialsFilePath == "" {
-		originCertDir := filepath.Dir(credential.certPath)
+		originCertDir := filepath.Dir(credential.CertPath())
 		credentialsFilePath, err = tunnelFilePath(tunnelCredentials.TunnelID, originCertDir)
 		if err != nil {
 			return nil, err

cmd/cloudflared/tunnel/subcommand_context_test.go

@@ -16,6 +16,7 @@ import (
 
 	"github.com/cloudflare/cloudflared/cfapi"
 	"github.com/cloudflare/cloudflared/connection"
+	"github.com/cloudflare/cloudflared/credentials"
 )
 
 type mockFileSystem struct {
@@ -37,7 +38,7 @@ func Test_subcommandContext_findCredentials(t *testing.T) {
 		log               *zerolog.Logger
 		fs                fileSystem
 		tunnelstoreClient cfapi.Client
-		userCredential    *userCredential
+		userCredential    *credentials.User
 	}
 	type args struct {
 		tunnelID uuid.UUID
@@ -249,7 +250,7 @@ func Test_subcommandContext_Delete(t *testing.T) {
 		isUIEnabled       bool
 		fs                fileSystem
 		tunnelstoreClient *deleteMockTunnelStore
-		userCredential    *userCredential
+		userCredential    *credentials.User
 	}
 	type args struct {
 		tunnelIDs []uuid.UUID