feat: establish secure update foundation

internal/updateagent/controller_test.go

@@ -56,9 +56,19 @@ func TestControllerValidatesRequestsAndRunsOnlyOneUpdate(t *testing.T) {
 	if trailing.Code != http.StatusBadRequest {
 		t.Fatalf("request with trailing JSON accepted: status=%d", trailing.Code)
 	}
+	invalidCurrent := httptest.NewRecorder()
+	handler.ServeHTTP(invalidCurrent, httptest.NewRequest(http.MethodPost, "/v1/update", strings.NewReader(`{"version":"v2.0.0","current_version":"1.3","registry_username":"user","registry_token":"secret-token"}`)))
+	if invalidCurrent.Code != http.StatusBadRequest {
+		t.Fatalf("invalid current version accepted: status=%d", invalidCurrent.Code)
+	}
+	missingCurrent := httptest.NewRecorder()
+	handler.ServeHTTP(missingCurrent, httptest.NewRequest(http.MethodPost, "/v1/update", strings.NewReader(`{"version":"v2.0.0","registry_username":"user","registry_token":"secret-token"}`)))
+	if missingCurrent.Code != http.StatusBadRequest {
+		t.Fatalf("request without current version accepted: status=%d", missingCurrent.Code)
+	}
 
 	const secret = "registry-token-must-not-leak"
-	body := []byte(`{"version":"v1.2.3","registry_username":"user","registry_token":"` + secret + `"}`)
+	body := []byte(`{"version":"v2.0.0","current_version":"v1.4.0","registry_username":"user","registry_token":"` + secret + `"}`)
 	accepted := httptest.NewRecorder()
 	handler.ServeHTTP(accepted, httptest.NewRequest(http.MethodPost, "/v1/update", bytes.NewReader(body)))
 	if accepted.Code != http.StatusAccepted {
@@ -66,7 +76,7 @@ func TestControllerValidatesRequestsAndRunsOnlyOneUpdate(t *testing.T) {
 	}
 	select {
 	case request := <-runner.started:
-		if request.Version != "v1.2.3" || request.RegistryToken != secret {
+		if request.Version != "v2.0.0" || request.CurrentVersion != "v1.4.0" || request.RegistryToken != secret {
 			t.Fatalf("runner received an altered request: %#v", request)
 		}
 	case <-time.After(time.Second):
@@ -80,7 +90,7 @@ func TestControllerValidatesRequestsAndRunsOnlyOneUpdate(t *testing.T) {
 	}
 	status := httptest.NewRecorder()
 	handler.ServeHTTP(status, httptest.NewRequest(http.MethodGet, "/v1/status", nil))
-	if status.Code != http.StatusOK || strings.Contains(status.Body.String(), secret) || !strings.Contains(status.Body.String(), `"phase":"pulling"`) {
+	if status.Code != http.StatusOK || strings.Contains(status.Body.String(), secret) || !strings.Contains(status.Body.String(), `"phase":"pulling"`) || !strings.Contains(status.Body.String(), `"protocol_version":2`) {
 		t.Fatalf("unsafe or invalid public status: status=%d body=%s", status.Code, status.Body.String())
 	}