TUN-3581: Tunnels can be run by name using only --credentials-file, no

origin cert necessary.

Author: adamchalmers

cmd/cloudflared/linux_service.go

@@ -12,6 +12,7 @@ import (
 
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/cliutil"
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/config"
+	"github.com/cloudflare/cloudflared/cmd/cloudflared/tunnel"
 	"github.com/cloudflare/cloudflared/logger"
 )
 
@@ -250,7 +251,7 @@ func installLinuxService(c *cli.Context) error {
 			val, err := src.String(s)
 			return err == nil && val != ""
 		}
-		if src.TunnelID == "" || !configPresent("credentials-file") {
+		if src.TunnelID == "" || !configPresent(tunnel.CredFileFlag) {
 			return fmt.Errorf(`Configuration file %s must contain entries for the tunnel to run and its associated credentials:
 tunnel: TUNNEL-UUID
 credentials-file: CREDENTIALS-FILE

cmd/cloudflared/tunnel/credential_finder.go

@@ -0,0 +1,78 @@
+package tunnel
+
+import (
+	"fmt"
+	"path/filepath"
+
+	"github.com/cloudflare/cloudflared/cmd/cloudflared/config"
+	"github.com/cloudflare/cloudflared/logger"
+	"github.com/google/uuid"
+	"github.com/urfave/cli/v2"
+)
+
+// CredFinder can find the tunnel credentials file.
+type CredFinder interface {
+	Path() (string, error)
+}
+
+// Implements CredFinder and looks for the credentials file at the given
+// filepath.
+type staticPath struct {
+	filePath string
+	fs       fileSystem
+}
+
+func newStaticPath(filePath string, fs fileSystem) CredFinder {
+	return staticPath{
+		filePath: filePath,
+		fs:       fs,
+	}
+}
+
+func (a staticPath) Path() (string, error) {
+	if a.filePath != "" && a.fs.validFilePath(a.filePath) {
+		return a.filePath, nil
+	}
+	return "", fmt.Errorf("Tunnel credentials file '%s' doesn't exist or is not a file", a.filePath)
+}
+
+// Implements CredFinder and looks for the credentials file in several directories
+// searching for a file named <id>.json
+type searchByID struct {
+	id     uuid.UUID
+	c      *cli.Context
+	logger logger.Service
+	fs     fileSystem
+}
+
+func newSearchByID(id uuid.UUID, c *cli.Context, logger logger.Service, fs fileSystem) CredFinder {
+	return searchByID{
+		id:     id,
+		c:      c,
+		logger: logger,
+		fs:     fs,
+	}
+}
+
+func (s searchByID) Path() (string, error) {
+
+	// Fallback to look for tunnel credentials in the origin cert directory
+	if originCertPath, err := findOriginCert(s.c, s.logger); err == nil {
+		originCertDir := filepath.Dir(originCertPath)
+		if filePath, err := tunnelFilePath(s.id, originCertDir); err == nil {
+			if s.fs.validFilePath(filePath) {
+				return filePath, nil
+			}
+		}
+	}
+
+	// Last resort look under default config directories
+	for _, configDir := range config.DefaultConfigSearchDirectories() {
+		if filePath, err := tunnelFilePath(s.id, configDir); err == nil {
+			if s.fs.validFilePath(filePath) {
+				return filePath, nil
+			}
+		}
+	}
+	return "", fmt.Errorf("Tunnel credentials file not found")
+}

cmd/cloudflared/tunnel/filesystem.go

@@ -0,0 +1,27 @@
+package tunnel
+
+import (
+	"io/ioutil"
+	"os"
+)
+
+// Abstract away details of reading files, so that SubcommandContext can read
+// from either the real filesystem, or a mock (when running unit tests).
+type fileSystem interface {
+	readFile(filePath string) ([]byte, error)
+	validFilePath(path string) bool
+}
+
+type realFileSystem struct{}
+
+func (fs realFileSystem) validFilePath(path string) bool {
+	fileStat, err := os.Stat(path)
+	if err != nil {
+		return false
+	}
+	return !fileStat.IsDir()
+}
+
+func (fs realFileSystem) readFile(filePath string) ([]byte, error) {
+	return ioutil.ReadFile(filePath)
+}

cmd/cloudflared/tunnel/subcommand_context.go

@@ -3,20 +3,16 @@ package tunnel
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
 	"os"
-	"path/filepath"
 	"strings"
 
 	"github.com/google/uuid"
 	"github.com/pkg/errors"
 	"github.com/urfave/cli/v2"
 
 	"github.com/cloudflare/cloudflared/certutil"
-	"github.com/cloudflare/cloudflared/cmd/cloudflared/config"
 	"github.com/cloudflare/cloudflared/connection"
 	"github.com/cloudflare/cloudflared/logger"
-	"github.com/cloudflare/cloudflared/tunnelrpc/pogs"
 	"github.com/cloudflare/cloudflared/tunnelstore"
 )
 
@@ -32,14 +28,14 @@ func (e errInvalidJSONCredential) Error() string {
 // subcommandContext carries structs shared between subcommands, to reduce number of arguments needed to
 // pass between subcommands, and make sure they are only initialized once
 type subcommandContext struct {
-	c      *cli.Context
-	logger logger.Service
+	c           *cli.Context
+	logger      logger.Service
+	isUIEnabled bool
+	fs          fileSystem
 
 	// These fields should be accessed using their respective Getter
 	tunnelstoreClient tunnelstore.Client
 	userCredential    *userCredential
-
-	isUIEnabled bool
 }
 
 func newSubcommandContext(c *cli.Context) (*subcommandContext, error) {
@@ -55,9 +51,18 @@ func newSubcommandContext(c *cli.Context) (*subcommandContext, error) {
 		c:           c,
 		logger:      logger,
 		isUIEnabled: isUIEnabled,
+		fs:          realFileSystem{},
 	}, nil
 }
 
+// Returns something that can find the given tunnel's credentials file.
+func (sc *subcommandContext) credentialFinder(tunnelID uuid.UUID) CredFinder {
+	if path := sc.c.String(CredFileFlag); path != "" {
+		return newStaticPath(path, sc.fs)
+	}
+	return newSearchByID(tunnelID, sc.c, sc.logger, sc.fs)
+}
+
 type userCredential struct {
 	cert     *certutil.OriginCert
 	certPath string
@@ -108,56 +113,27 @@ func (sc *subcommandContext) credential() (*userCredential, error) {
 	return sc.userCredential, nil
 }
 
-func (sc *subcommandContext) readTunnelCredentials(tunnelID uuid.UUID) (*pogs.TunnelAuth, error) {
-	filePath, err := sc.tunnelCredentialsPath(tunnelID)
+func (sc *subcommandContext) readTunnelCredentials(credFinder CredFinder) (connection.Credentials, error) {
+	filePath, err := credFinder.Path()
 	if err != nil {
-		return nil, err
+		return connection.Credentials{}, err
 	}
-	body, err := ioutil.ReadFile(filePath)
+	body, err := sc.fs.readFile(filePath)
 	if err != nil {
-		return nil, errors.Wrapf(err, "couldn't read tunnel credentials from %v", filePath)
+		return connection.Credentials{}, errors.Wrapf(err, "couldn't read tunnel credentials from %v", filePath)
 	}
 
-	var auth pogs.TunnelAuth
-	if err = json.Unmarshal(body, &auth); err != nil {
+	var credentials connection.Credentials
+	if err = json.Unmarshal(body, &credentials); err != nil {
 		if strings.HasSuffix(filePath, ".pem") {
-			return nil, fmt.Errorf("The tunnel credentials file should be .json but you gave a .pem. "+
-				"The tunnel credentials file was originally created by `cloudflared tunnel create` and named %s.json."+
-				"You may have accidentally used the filepath to cert.pem, which is generated by `cloudflared tunnel "+
-				"login`.", tunnelID)
+			return connection.Credentials{}, fmt.Errorf("The tunnel credentials file should be .json but you gave a .pem. " +
+				"The tunnel credentials file was originally created by `cloudflared tunnel create`. " +
+				"You may have accidentally used the filepath to cert.pem, which is generated by `cloudflared tunnel " +
+				"login`.")
 		}
-		return nil, errInvalidJSONCredential{path: filePath, err: err}
+		return connection.Credentials{}, errInvalidJSONCredential{path: filePath, err: err}
 	}
-	return &auth, nil
-}
-
-func (sc *subcommandContext) tunnelCredentialsPath(tunnelID uuid.UUID) (string, error) {
-	if filePath := sc.c.String("credentials-file"); filePath != "" {
-		if validFilePath(filePath) {
-			return filePath, nil
-		}
-		return "", fmt.Errorf("Tunnel credentials file %s doesn't exist or is not a file", filePath)
-	}
-
-	// Fallback to look for tunnel credentials in the origin cert directory
-	if originCertPath, err := findOriginCert(sc.c, sc.logger); err == nil {
-		originCertDir := filepath.Dir(originCertPath)
-		if filePath, err := tunnelFilePath(tunnelID, originCertDir); err == nil {
-			if validFilePath(filePath) {
-				return filePath, nil
-			}
-		}
-	}
-
-	// Last resort look under default config directories
-	for _, configDir := range config.DefaultConfigSearchDirectories() {
-		if filePath, err := tunnelFilePath(tunnelID, configDir); err == nil {
-			if validFilePath(filePath) {
-				return filePath, nil
-			}
-		}
-	}
-	return "", fmt.Errorf("Tunnel credentials file not found")
+	return credentials, nil
 }
 
 func (sc *subcommandContext) create(name string) (*tunnelstore.Tunnel, error) {
@@ -180,7 +156,14 @@ func (sc *subcommandContext) create(name string) (*tunnelstore.Tunnel, error) {
 	if err != nil {
 		return nil, err
 	}
-	if writeFileErr := writeTunnelCredentials(tunnel.ID, credential.cert.AccountID, credential.certPath, tunnelSecret, sc.logger); err != nil {
+	tunnelCredentials := connection.Credentials{
+		AccountTag:   credential.cert.AccountID,
+		TunnelSecret: tunnelSecret,
+		TunnelID:     tunnel.ID,
+		TunnelName:   name,
+	}
+	filePath, writeFileErr := writeTunnelCredentials(credential.certPath, &tunnelCredentials)
+	if err != nil {
 		var errorLines []string
 		errorLines = append(errorLines, fmt.Sprintf("Your tunnel '%v' was created with ID %v. However, cloudflared couldn't write to the tunnel credentials file at %v.json.", tunnel.Name, tunnel.ID, tunnel.ID))
 		errorLines = append(errorLines, fmt.Sprintf("The file-writing error is: %v", writeFileErr))
@@ -193,6 +176,7 @@ func (sc *subcommandContext) create(name string) (*tunnelstore.Tunnel, error) {
 		errorMsg := strings.Join(errorLines, "\n")
 		return nil, errors.New(errorMsg)
 	}
+	sc.logger.Infof("Tunnel credentials written to %v. cloudflared chose this file based on where your origin certificate was found. Keep this file secret. To revoke these credentials, delete the tunnel.", filePath)
 
 	if outputFormat := sc.c.String(outputFormatFlag.Name); outputFormat != "" {
 		return nil, renderOutput(outputFormat, &tunnel)
@@ -243,7 +227,8 @@ func (sc *subcommandContext) delete(tunnelIDs []uuid.UUID) error {
 			return errors.Wrapf(err, "Error deleting tunnel %s", tunnel.ID)
 		}
 
-		tunnelCredentialsPath, err := sc.tunnelCredentialsPath(tunnel.ID)
+		credFinder := sc.credentialFinder(id)
+		tunnelCredentialsPath, err := credFinder.Path()
 		if err != nil {
 			sc.logger.Infof("Cannot locate tunnel credentials to delete, error: %v. Please delete the file manually", err)
 			return nil
@@ -256,22 +241,34 @@ func (sc *subcommandContext) delete(tunnelIDs []uuid.UUID) error {
 	return nil
 }
 
+// findCredentials will choose the right way to find the credentials file, find it,
+// and add the TunnelID into any old credentials (generated before TUN-3581 added the `TunnelID`
+// field to credentials files)
+func (sc *subcommandContext) findCredentials(tunnelID uuid.UUID) (connection.Credentials, error) {
+	credFinder := sc.credentialFinder(tunnelID)
+	credentials, err := sc.readTunnelCredentials(credFinder)
+	// This line ensures backwards compatibility with credentials files generated before
+	// TUN-3581. Those old credentials files don't have a TunnelID field, so we enrich the struct
+	// with the ID, which we have already resolved from the user input.
+	credentials.TunnelID = tunnelID
+	return credentials, err
+}
+
 func (sc *subcommandContext) run(tunnelID uuid.UUID) error {
-	credentials, err := sc.readTunnelCredentials(tunnelID)
+	credentials, err := sc.findCredentials(tunnelID)
 	if err != nil {
 		if e, ok := err.(errInvalidJSONCredential); ok {
 			sc.logger.Errorf("The credentials file at %s contained invalid JSON. This is probably caused by passing the wrong filepath. Reminder: the credentials file is a .json file created via `cloudflared tunnel create`.", e.path)
 			sc.logger.Errorf("Invalid JSON when parsing credentials file: %s", e.err.Error())
 		}
 		return err
 	}
-
 	return StartServer(
 		sc.c,
 		version,
 		shutdownC,
 		graceShutdownC,
-		&connection.NamedTunnelConfig{Auth: *credentials, ID: tunnelID},
+		&connection.NamedTunnelConfig{Credentials: credentials},
 		sc.logger,
 		sc.isUIEnabled,
 	)
@@ -300,6 +297,7 @@ func (sc *subcommandContext) route(tunnelID uuid.UUID, r tunnelstore.Route) (tun
 	return client.RouteTunnel(tunnelID, r)
 }
 
+// Query Tunnelstore to find the active tunnel with the given name.
 func (sc *subcommandContext) tunnelActive(name string) (*tunnelstore.Tunnel, bool, error) {
 	filter := tunnelstore.NewFilter()
 	filter.NoDeleted()
@@ -322,6 +320,15 @@ func (sc *subcommandContext) findID(input string) (uuid.UUID, error) {
 		return u, nil
 	}
 
+	// Look up name in the credentials file.
+	credFinder := newStaticPath(sc.c.String(CredFileFlag), sc.fs)
+	if credentials, err := sc.readTunnelCredentials(credFinder); err == nil {
+		if credentials.TunnelID != uuid.Nil && input == credentials.TunnelName {
+			return credentials.TunnelID, nil
+		}
+	}
+
+	// Fall back to querying Tunnelstore.
 	if tunnel, found, err := sc.tunnelActive(input); err != nil {
 		return uuid.Nil, err
 	} else if found {