initial commit

tests/integration/helper_totp_code_at.go

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2026 Fluxer Contributors
+ *
+ * This file is part of Fluxer.
+ *
+ * Fluxer is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Fluxer is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with Fluxer. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package integration
+
+import (
+	"crypto/hmac"
+	"crypto/sha1"
+	"encoding/base32"
+	"encoding/binary"
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+)
+
+func totpCodeAt(t testing.TB, secret string, at time.Time) string {
+	t.Helper()
+	decoder := base32.StdEncoding.WithPadding(base32.NoPadding)
+	normalized := strings.ToUpper(strings.ReplaceAll(secret, " ", ""))
+	key, err := decoder.DecodeString(normalized)
+	if err != nil {
+		t.Fatalf("failed to decode totp secret: %v", err)
+	}
+
+	counter := uint64(at.Unix() / 30)
+	var counterBytes [8]byte
+	binary.BigEndian.PutUint64(counterBytes[:], counter)
+
+	mac := hmac.New(sha1.New, key)
+	if _, err := mac.Write(counterBytes[:]); err != nil {
+		t.Fatalf("failed to compute totp hmac: %v", err)
+	}
+	sum := mac.Sum(nil)
+	offset := sum[len(sum)-1] & 0x0f
+	code := ((int(sum[offset]) & 0x7f) << 24) |
+		((int(sum[offset+1]) & 0xff) << 16) |
+		((int(sum[offset+2]) & 0xff) << 8) |
+		(int(sum[offset+3]) & 0xff)
+	code %= 1000000
+	return fmt.Sprintf("%06d", code)
+}