Sub2API v1.0 - AI API 网关（二开初始版本，基于上游 Wei-Shaw/sub2api）

backend/internal/server/middleware/request_metadata.go

@@ -0,0 +1,30 @@
+package middleware
+
+import (
+	"strings"
+	"unicode/utf8"
+)
+
+const (
+	maxPersistentRequestIDBytes = 64
+	maxPersistentUserAgentBytes = 512
+)
+
+// normalizePersistentText bounds attacker-controlled metadata before it reaches
+// logs or database columns while preserving valid UTF-8 content.
+func normalizePersistentText(value string, maxBytes int) string {
+	value = strings.TrimSpace(strings.ToValidUTF8(value, ""))
+	if maxBytes <= 0 || len(value) <= maxBytes {
+		return value
+	}
+	value = value[:maxBytes]
+	for !utf8.ValidString(value) {
+		value = value[:len(value)-1]
+	}
+	return value
+}
+
+func normalizeCorrelationID(value string) (string, bool) {
+	value = strings.TrimSpace(strings.ToValidUTF8(value, ""))
+	return value, value != "" && len(value) <= maxPersistentRequestIDBytes
+}