Fixes in-memory keyring initialization so gossip encryption still works.

Fixes #3243.

agent/agent.go

@@ -794,10 +794,9 @@ func (a *Agent) consulConfig() (*consul.Config, error) {
 	// Setup the loggers
 	base.LogOutput = a.LogOutput
 
-	if !a.config.DisableKeyringFile {
-		if err := a.setupKeyrings(base); err != nil {
-			return nil, fmt.Errorf("Failed to configure keyring: %v", err)
-		}
+	// This will set up the LAN keyring, as well as the WAN for servers.
+	if err := a.setupKeyrings(base); err != nil {
+		return nil, fmt.Errorf("Failed to configure keyring: %v", err)
 	}
 
 	return base, nil
@@ -1026,6 +1025,26 @@ func (a *Agent) setupNodeID(config *Config) error {
 
 // setupKeyrings is used to initialize and load keyrings during agent startup
 func (a *Agent) setupKeyrings(config *consul.Config) error {
+	// If the keyring file is disabled then just poke the provided key
+	// into the in-memory keyring.
+	if a.config.DisableKeyringFile {
+		if a.config.EncryptKey == "" {
+			return nil
+		}
+
+		keys := []string{a.config.EncryptKey}
+		if err := loadKeyring(config.SerfLANConfig, keys); err != nil {
+			return err
+		}
+		if a.config.Server {
+			if err := loadKeyring(config.SerfWANConfig, keys); err != nil {
+				return err
+			}
+		}
+		return nil
+	}
+
+	// Otherwise, we need to deal with the keyring files.
 	fileLAN := filepath.Join(a.config.DataDir, SerfLANKeyring)
 	fileWAN := filepath.Join(a.config.DataDir, SerfWANKeyring)
 
@@ -1061,7 +1080,6 @@ LOAD:
 		}
 	}
 
-	// Success!
 	return nil
 }
 

agent/keyring.go

@@ -69,19 +69,22 @@ func loadKeyringFile(c *serf.Config) error {
 		return err
 	}
 
-	// Read in the keyring file data
 	keyringData, err := ioutil.ReadFile(c.KeyringFile)
 	if err != nil {
 		return err
 	}
 
-	// Decode keyring JSON
 	keys := make([]string, 0)
 	if err := json.Unmarshal(keyringData, &keys); err != nil {
 		return err
 	}
 
-	// Decode base64 values
+	return loadKeyring(c, keys)
+}
+
+// loadKeyring takes a list of base64-encoded strings and installs them in the
+// given Serf's keyring.
+func loadKeyring(c *serf.Config, keys []string) error {
 	keysDecoded := make([][]byte, len(keys))
 	for i, key := range keys {
 		keyBytes, err := base64.StdEncoding.DecodeString(key)
@@ -91,20 +94,16 @@ func loadKeyringFile(c *serf.Config) error {
 		keysDecoded[i] = keyBytes
 	}
 
-	// Guard against empty keyring
 	if len(keysDecoded) == 0 {
-		return fmt.Errorf("no keys present in keyring file: %s", c.KeyringFile)
+		return fmt.Errorf("no keys present in keyring: %s", c.KeyringFile)
 	}
 
-	// Create the keyring
 	keyring, err := memberlist.NewKeyring(keysDecoded, keysDecoded[0])
 	if err != nil {
 		return err
 	}
 
 	c.MemberlistConfig.Keyring = keyring
-
-	// Success!
 	return nil
 }
 

agent/keyring_test.go

@@ -74,6 +74,75 @@ func TestAgent_LoadKeyrings(t *testing.T) {
 	}
 }
 
+func TestAgent_InmemKeyrings(t *testing.T) {
+	t.Parallel()
+	key := "tbLJg26ZJyJ9pK3qhc9jig=="
+
+	// Should be no configured keyring file by default
+	a1 := NewTestAgent(t.Name(), nil)
+	defer a1.Shutdown()
+
+	c1 := a1.Config.ConsulConfig
+	if c1.SerfLANConfig.KeyringFile != "" {
+		t.Fatalf("bad: %#v", c1.SerfLANConfig.KeyringFile)
+	}
+	if c1.SerfLANConfig.MemberlistConfig.Keyring != nil {
+		t.Fatalf("keyring should not be loaded")
+	}
+	if c1.SerfWANConfig.KeyringFile != "" {
+		t.Fatalf("bad: %#v", c1.SerfLANConfig.KeyringFile)
+	}
+	if c1.SerfWANConfig.MemberlistConfig.Keyring != nil {
+		t.Fatalf("keyring should not be loaded")
+	}
+
+	cfg2 := TestConfig()
+	cfg2.EncryptKey = key
+	cfg2.DisableKeyringFile = true
+
+	// Server should auto-load LAN and WAN keyring
+	a2 := &TestAgent{Name: t.Name(), Config: cfg2}
+	a2.Start()
+	defer a2.Shutdown()
+
+	c2 := a2.Config.ConsulConfig
+	if c2.SerfLANConfig.KeyringFile != "" {
+		t.Fatalf("should not have keyring file")
+	}
+	if c2.SerfLANConfig.MemberlistConfig.Keyring == nil {
+		t.Fatalf("keyring should be loaded")
+	}
+	if c2.SerfWANConfig.KeyringFile != "" {
+		t.Fatalf("should not have keyring file")
+	}
+	if c2.SerfWANConfig.MemberlistConfig.Keyring == nil {
+		t.Fatalf("keyring should be loaded")
+	}
+
+	// Client should auto-load only the LAN keyring
+	cfg3 := TestConfig()
+	cfg3.EncryptKey = key
+	cfg3.DisableKeyringFile = true
+	cfg3.Server = false
+	a3 := &TestAgent{Name: t.Name(), Config: cfg3}
+	a3.Start()
+	defer a3.Shutdown()
+
+	c3 := a3.Config.ConsulConfig
+	if c3.SerfLANConfig.KeyringFile != "" {
+		t.Fatalf("should not have keyring file")
+	}
+	if c3.SerfLANConfig.MemberlistConfig.Keyring == nil {
+		t.Fatalf("keyring should be loaded")
+	}
+	if c3.SerfWANConfig.KeyringFile != "" {
+		t.Fatalf("bad: %#v", c3.SerfWANConfig.KeyringFile)
+	}
+	if c3.SerfWANConfig.MemberlistConfig.Keyring != nil {
+		t.Fatalf("keyring should not be loaded")
+	}
+}
+
 func TestAgent_InitKeyring(t *testing.T) {
 	t.Parallel()
 	key1 := "tbLJg26ZJyJ9pK3qhc9jig=="