cmd/stepd: Load plugins from STEP_PLUGIN_PATH

cmd/stepd/main.go

@@ -116,6 +116,23 @@ func main () {
 	if err != nil { log.Fatal(err) }
 
 	// TODO: load plugins
+	pluginPath := os.Getenv("STEP_PLUGIN_PATH")
+	if pluginPath == "" {
+		pluginPath = "/usr/lib/step/plugins:/usr/local/lib/step/plugins"
+	}
+	for _, pat := range filepath.SplitList(pluginPath) {
+		entries, err := os.ReadDir(pat)
+		if err != nil { continue }
+		for _, entry := range entries {
+			pluginPath := filepath.Join(pat, entry.Name())
+			_, err := environment.LoadProviderPlugin(pat)
+			if err != nil {
+				log.Printf (
+					"!!! could not load plugin %s: %v",
+					pluginPath, err)
+			}
+		}
+	}
 	logProviders(environment.Providers)
 
 	// set up the HTTP handler