Initial commit: NetMesh smart ops platform with 3D topology, inspection reports, RCA and AI ops assistant

lib/regexSafety.ts

@@ -0,0 +1,19 @@
+/**
+ * Best-effort regex safety guard for user-provided patterns.
+ *
+ * Reject nested quantifier shapes such as `(a+)+`, `(a*)*`, `(a+){2,}`
+ * that are common catastrophic-backtracking sources.
+ */
+export type RegexSafetyReason = "nested_quantifier";
+
+export type RegexSafetyCheckResult =
+  | { safe: true }
+  | { safe: false; reason: RegexSafetyReason };
+
+export function checkRegexSafetyPattern(pattern: string): RegexSafetyCheckResult {
+  const nestedUnboundedQuantifier = /\((?:\?:)?[^)]*(?:\+|\*|\{\d+,\}|\{,\d+\})[^)]*\)(?:\+|\*|\{\d+,\}|\{,\d+\})/;
+  if (nestedUnboundedQuantifier.test(pattern)) {
+    return { safe: false, reason: "nested_quantifier" };
+  }
+  return { safe: true };
+}