js-firewall-creatorseojun-123/index.js

실시간 사용자 행동을 분석하여 보안 위협을 감지하는 JS 라이브러리

const BehavioralFirewall = (() => {
  let config = {
    mode: "strict",
    onDetected: (type) => console.warn("[Firewall] Threat Detection:", type),
    reportUrl: null,
  };

  let lastClick = 0;
  let mouseMoves = 0;
  let keyPresses = 0;
  let startTime = Date.now();
  let lastActivityTime = Date.now();
  let idleCheckInterval;

  let lastMouseX = null;
  let lastMouseY = null;
  let lastMouseMoveTime = null;

  function init(userConfig) {
    config = { ...config, ...userConfig };

    document.addEventListener("click", handleClick);
    document.addEventListener("mousemove", handleMouseMove);
    document.addEventListener("keydown", handleKeyPress);
    window.addEventListener("blur", () => report("tab-blur"));

    idleCheckInterval = setInterval(checkIdle, 10000);
  }

  function handleClick() {
    const now = Date.now();
    if (now - lastClick < 50) {
      report("click-spam");
    }
    lastClick = now;
    lastActivityTime = now;
  }

  function handleMouseMove(event) {
    const now = Date.now();
    mouseMoves++;
    lastActivityTime = now;

    if (lastMouseX !== null && lastMouseY !== null && lastMouseMoveTime !== null) {
      const dx = event.screenX - lastMouseX;
      const dy = event.screenY - lastMouseY;
      const dt = now - lastMouseMoveTime;
      const distance = Math.sqrt(dx * dx + dy * dy);
      const speed = distance / dt; // px/ms

      if (speed > 35) {
        report("mouse-speed-abnormal");
      }
    }

    lastMouseX = event.screenX;
    lastMouseY = event.screenY;
    lastMouseMoveTime = now;
  }

  function handleKeyPress() {
    keyPresses++;
    lastActivityTime = Date.now();
  }

  function checkIdle() {
    const now = Date.now();
    const idleTime = (now - lastActivityTime) / 1000;

    if (idleTime >= 90) {
      report("idle-over-90sec");
    }

    const elapsed = (now - startTime) / 1000;
    if (elapsed > 5) {
      if (mouseMoves === 0) {
        report("no-mouse-activity");
      }
      if (keyPresses === 0 && mouseMoves > 10) {
        report("no-typing-with-activity");
      }
      mouseMoves = 0;
      keyPresses = 0;
      startTime = now;
    }
  }

  function report(type) {
    if (config.mode === "strict") {
      config.onDetected(type);
      if (config.reportUrl) {
        try {
          fetch(config.reportUrl, {
            method: "POST",
            headers: { "Content-Type": "application/json" },
            body: JSON.stringify({
              type,
              timestamp: new Date().toISOString(),
              userAgent: navigator.userAgent
            })
          }).catch(err => console.error("[Firewall] Server transfer failure (catch):", err));
        } catch (err) {
          console.error("[Firewall] Server transfer failure (try):", err);
        }
      }
    } else {
      console.log("[Firewall] Server transfer failure:", type);
    }
  }

  function stop() {
    clearInterval(idleCheckInterval);
    document.removeEventListener("click", handleClick);
    document.removeEventListener("mousemove", handleMouseMove);
    document.removeEventListener("keydown", handleKeyPress);
  }

  return { init, stop };
})();