diff --git a/backend/package.json b/backend/package.json
index 7749351..45c5615 100644
--- a/backend/package.json
+++ b/backend/package.json
@@ -1,6 +1,6 @@
 {
   "name": "sub-store",
-  "version": "2.14.194",
+  "version": "2.14.195",
   "description": "Advanced Subscription Manager for QX, Loon, Surge, Stash and ShadowRocket.",
   "main": "src/main.js",
   "scripts": {
diff --git a/backend/src/core/proxy-utils/processors/index.js b/backend/src/core/proxy-utils/processors/index.js
index 449b101..ed115b7 100644
--- a/backend/src/core/proxy-utils/processors/index.js
+++ b/backend/src/core/proxy-utils/processors/index.js
@@ -14,6 +14,7 @@ import {
     getFlowField,
     getFlowHeaders,
     parseFlowHeaders,
+    validCheck,
     flowTransfer,
 } from '@/utils/flow';
 
@@ -806,6 +807,7 @@ function createDynamicFunction(name, script, $arguments) {
         getFlowHeaders,
         parseFlowHeaders,
         flowTransfer,
+        validCheck,
     };
     if ($.env.isLoon) {
         return new Function(
diff --git a/backend/src/utils/download.js b/backend/src/utils/download.js
index 9b59459..f1f7c80 100644
--- a/backend/src/utils/download.js
+++ b/backend/src/utils/download.js
@@ -4,7 +4,12 @@ import { HTTP, ENV } from '@/vendor/open-api';
 import { hex_md5 } from '@/vendor/md5';
 import resourceCache from '@/utils/resource-cache';
 import headersResourceCache from '@/utils/headers-resource-cache';
-import { getFlowField } from '@/utils/flow';
+import {
+    getFlowField,
+    getFlowHeaders,
+    parseFlowHeaders,
+    validCheck,
+} from '@/utils/flow';
 import $ from '@/core/app';
 
 const tasks = new Map();
@@ -64,36 +69,40 @@ export default async function download(rawUrl, ua, timeout) {
         timeout: requestTimeout,
     });
 
-    const result = new Promise((resolve, reject) => {
-        // try to find in app cache
-        const cached = resourceCache.get(id);
-        if (!$arguments?.noCache && cached) {
-            resolve(cached);
-        } else {
-            $.info(
-                `Downloading...\nUser-Agent: ${userAgent}\nTimeout: ${requestTimeout}\nURL: ${url}`,
-            );
-            http.get(url)
-                .then((resp) => {
-                    const { body, headers } = resp;
-                    if (headers) {
-                        const flowInfo = getFlowField(headers);
-                        if (flowInfo) {
-                            headersResourceCache.set(url, flowInfo);
-                        }
-                    }
-                    if (body.replace(/\s/g, '').length === 0)
-                        reject(new Error('远程资源内容为空！'));
-                    else {
-                        resourceCache.set(id, body);
-                        resolve(body);
-                    }
-                })
-                .catch(() => {
-                    reject(new Error(`无法下载 URL：${url}`));
-                });
+    let result;
+
+    // try to find in app cache
+    const cached = resourceCache.get(id);
+    if (!$arguments?.noCache && cached) {
+        result = cached;
+    } else {
+        $.info(
+            `Downloading...\nUser-Agent: ${userAgent}\nTimeout: ${requestTimeout}\nURL: ${url}`,
+        );
+        try {
+            const { body, headers } = await http.get(url);
+
+            if (headers) {
+                const flowInfo = getFlowField(headers);
+                if (flowInfo) {
+                    headersResourceCache.set(url, flowInfo);
+                }
+            }
+            if (body.replace(/\s/g, '').length === 0)
+                throw new Error(new Error('远程资源内容为空'));
+
+            resourceCache.set(id, body);
+            result = body;
+        } catch (e) {
+            throw new Error(`无法下载 URL ${url}: ${e.message ?? e}`);
         }
-    });
+    }
+
+    // 检查订阅有效性
+
+    if ($arguments?.validCheck) {
+        await validCheck(parseFlowHeaders(await getFlowHeaders(url)));
+    }
 
     if (!isNode) {
         tasks.set(id, result);
diff --git a/backend/src/utils/flow.js b/backend/src/utils/flow.js
index 6414a38..8c8116a 100644
--- a/backend/src/utils/flow.js
+++ b/backend/src/utils/flow.js
@@ -120,3 +120,26 @@ export function flowTransfer(flow, unit = 'B') {
         ? { value: flow.toFixed(1), unit: unit }
         : flowTransfer(flow / 1024, unitList[++unitIndex]);
 }
+
+export function validCheck(flow) {
+    if (!flow) {
+        throw new Error('没有流量信息');
+    }
+    if (flow?.expires && flow.expires * 1000 < Date.now()) {
+        const date = new Date(flow.expires * 1000).toLocaleDateString();
+        throw new Error(`订阅已过期: ${date}`);
+    }
+    if (flow?.total) {
+        const upload = flow.usage?.upload || 0;
+        const download = flow.usage?.download || 0;
+        if (flow.total - upload - download < 0) {
+            const current = upload + download;
+            const currT = flowTransfer(Math.abs(current));
+            currT.value = current < 0 ? '-' + currT.value : currT.value;
+            const totalT = flowTransfer(flow.total);
+            throw new Error(
+                `流量已用完: ${currT.value} ${currT.unit} / ${totalT.value} ${totalT.unit}`,
+            );
+        }
+    }
+}