Enable Feishu session username override with OpenVPN 2.7

backend/internal/service/openvpn/oidc.go

@@ -60,13 +60,35 @@ func yamlString(s string) string {
 	return string(b)
 }
 
-func oidcConfig(t *model.Tunnel, cfg map[string]interface{}) string {
+func supportsOverrideUsername() bool {
+	bin, ok := findOpenVPNBin()
+	if !ok {
+		return false
+	}
+	out, err := exec.Command(bin, "--version").Output()
+	if err != nil {
+		return false
+	}
+	m := regexp.MustCompile(`OpenVPN\s+(\d+)\.(\d+)\.(\d+)`).FindSubmatch(out)
+	if len(m) != 4 {
+		return false
+	}
+	major, _ := strconv.Atoi(string(m[1]))
+	minor, _ := strconv.Atoi(string(m[2]))
+	return major > 2 || major == 2 && minor >= 7
+}
+
+func oidcConfig(t *model.Tunnel, cfg map[string]interface{}, overrideUsername bool) string {
 	dir := service.InstanceDir(t)
 	usernameConfig := ""
+	overrideConfig := ""
 	if service.Str(cfg, "oidc_provider") == "builtin" {
 		usernameConfig = "  openvpn-username: \"string(token.claims.sub)\"\n"
+		if overrideUsername {
+			overrideConfig = "  override-username: true\n"
+		}
 	}
-	return fmt.Sprintf("http:\n  baseurl: %s\n  listen: %s\n  secret: %s\n  template: %s\noauth2:\n%s  issuer: %s\n  client:\n    id: %s\n    secret: %s\nopenvpn:\n  addr: %s\n  password: %s\n  auth-token-user: true\n",
+	return fmt.Sprintf("http:\n  baseurl: %s\n  listen: %s\n  secret: %s\n  template: %s\noauth2:\n%s  issuer: %s\n  client:\n    id: %s\n    secret: %s\nopenvpn:\n%s  addr: %s\n  password: %s\n  auth-token-user: true\n",
 		yamlString(service.Str(cfg, "oidc_base_url")),
 		yamlString(fmt.Sprintf("127.0.0.1:%d", int(service.Num(cfg, "oidc_http_port", 19090)))),
 		yamlString(service.Str(cfg, "oidc_http_secret")),
@@ -75,6 +97,7 @@ func oidcConfig(t *model.Tunnel, cfg map[string]interface{}) string {
 		yamlString(service.Str(cfg, "oidc_issuer")),
 		yamlString(service.Str(cfg, "oidc_client_id")),
 		yamlString(service.Str(cfg, "oidc_client_secret")),
+		overrideConfig,
 		yamlString("unix://"+filepath.Join(dir, "management.sock")),
 		yamlString(service.Str(cfg, "oidc_management_password")))
 }
@@ -153,7 +176,7 @@ func prepareOIDC(t *model.Tunnel, cfg map[string]interface{}) error {
 	if err := os.Chmod(pagePath, 0o600); err != nil {
 		return err
 	}
-	configPath, err := service.WriteConfig(t, "openvpn-auth-oauth2.yaml", oidcConfig(t, cfg))
+	configPath, err := service.WriteConfig(t, "openvpn-auth-oauth2.yaml", oidcConfig(t, cfg, supportsOverrideUsername()))
 	if err != nil {
 		return err
 	}