fix: 修复并统一 VLESS XHTTP 的 host/mode 映射与继承

解析器与生成器同步处理 xhttp-opts 的 mode，避免空值字段被误判为非法

把 Host 头与 URI 的 host 参数分离，避免回写混淆

download-settings 支持从外层 xhttp-opts 继承 path/host/mode

同步更新 parser/producer 相关测试，覆盖下载设置与回写场景

Author: xream

backend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "sub-store",
-  "version": "2.22.9",
+  "version": "2.22.10",
   "description": "Advanced Subscription Manager for QX, Loon, Surge, Stash and Shadowrocket.",
   "main": "src/main.js",
   "scripts": {

backend/src/core/proxy-utils/parsers/index.js

@@ -1036,9 +1036,20 @@ function URI_VLESS() {
                 );
             }
 
+            if (
+                Object.prototype.hasOwnProperty.call(xhttpSettings, 'mode') &&
+                !isNotBlank(xhttpSettings.mode)
+            ) {
+                setUnsupportedXhttpField(
+                    unsupportedXhttpSettings,
+                    'mode',
+                    xhttpSettings.mode,
+                );
+            }
+
             const inlineExtra = {};
             for (const [key, value] of Object.entries(xhttpSettings)) {
-                if (['path', 'host', 'extra'].includes(key)) {
+                if (['path', 'host', 'mode', 'extra'].includes(key)) {
                     continue;
                 }
                 inlineExtra[key] = value;
@@ -1098,7 +1109,9 @@ function URI_VLESS() {
                         break;
                     case 'security': {
                         const normalizedSecurity =
-                            typeof value === 'string' ? value.toLowerCase() : '';
+                            typeof value === 'string'
+                                ? value.toLowerCase()
+                                : '';
                         if (!['tls', 'reality'].includes(normalizedSecurity)) {
                             setUnsupportedXhttpField(
                                 unsupportedDownloadSettings,
@@ -1119,7 +1132,9 @@ function URI_VLESS() {
                         }
 
                         const unsupportedTlsSettings = {};
-                        for (const [tlsKey, tlsValue] of Object.entries(value)) {
+                        for (const [tlsKey, tlsValue] of Object.entries(
+                            value,
+                        )) {
                             switch (tlsKey) {
                                 case 'serverName':
                                 case 'fingerprint':
@@ -1238,7 +1253,9 @@ function URI_VLESS() {
                     }
                     case 'network': {
                         const normalizedNetwork =
-                            typeof value === 'string' ? value.toLowerCase() : '';
+                            typeof value === 'string'
+                                ? value.toLowerCase()
+                                : '';
                         if (
                             normalizedNetwork !== 'xhttp' &&
                             normalizedNetwork !== 'splithttp'
@@ -1501,6 +1518,10 @@ function URI_VLESS() {
                     parsedDownloadSettings.host =
                         downloadSettings.xhttpSettings.host;
                 }
+                if (isNotBlank(downloadSettings.xhttpSettings.mode)) {
+                    parsedDownloadSettings.mode =
+                        downloadSettings.xhttpSettings.mode;
+                }
                 applyXhttpExtraFields(
                     parsedDownloadSettings,
                     downloadSettings.xhttpSettings,
@@ -1651,6 +1672,13 @@ function URI_VLESS() {
                 } else {
                     opts.headers = { Host: host };
                 }
+                if (['xhttp'].includes(proxy.network) && opts.headers?.Host) {
+                    opts.host = opts.headers.Host;
+                    delete opts.headers.Host;
+                    if (Object.keys(opts.headers).length === 0) {
+                        delete opts.headers;
+                    }
+                }
             }
             if (params.serviceName) {
                 opts[`${proxy.network}-service-name`] = params.serviceName;
@@ -1753,9 +1781,12 @@ function URI_VLESS() {
                 // Supported fields must round-trip through the structured node
                 // so later edits are reflected on export, while unsupported
                 // fields still survive VLESS URI -> node -> VLESS URI flows.
-                const unsupportedExtra = collectUnsupportedRootXhttpExtra(extra, {
-                    parsedDownloadSettings: downloadSettings,
-                });
+                const unsupportedExtra = collectUnsupportedRootXhttpExtra(
+                    extra,
+                    {
+                        parsedDownloadSettings: downloadSettings,
+                    },
+                );
                 if (unsupportedExtra) {
                     proxy._extra_unsupported = unsupportedExtra;
                 }

backend/src/core/proxy-utils/producers/uri.js

@@ -191,7 +191,7 @@ function applyStructuredXhttpExtraFields(
     }
 }
 
-function buildXhttpDownloadSettings(downloadSettings) {
+function buildXhttpDownloadSettings(downloadSettings, outerXhttpOpts = {}) {
     if (!isPlainObject(downloadSettings)) {
         return undefined;
     }
@@ -271,13 +271,23 @@ function buildXhttpDownloadSettings(downloadSettings) {
     }
 
     const xhttpSettings = {};
-    if (downloadSettings.path) {
-        xhttpSettings.path = downloadSettings.path;
-    }
-    const downloadHost = getTransportHost('xhttp', downloadSettings);
+    // Mirror Mihomo's inheritance: path and host fall back to outer xhttp-opts
+    // when not explicitly set in download-settings. Mode is never a field in
+    // Mihomo's XHTTPDownloadSettings struct, so it always comes from outer.
+    const dsPath = downloadSettings.path ?? outerXhttpOpts.path;
+    if (dsPath) {
+        xhttpSettings.path = dsPath;
+    }
+    const downloadHost =
+        getTransportHost('xhttp', downloadSettings) ??
+        getTransportHost('xhttp', outerXhttpOpts);
     if (downloadHost) {
         xhttpSettings.host = downloadHost;
     }
+    const mode = downloadSettings.mode ?? outerXhttpOpts.mode;
+    if (mode) {
+        xhttpSettings.mode = mode;
+    }
     applyStructuredXhttpExtraFields(xhttpSettings, downloadSettings, {
         excludeHostHeader: true,
         xmuxTarget: 'extra',
@@ -298,11 +308,15 @@ function buildXhttpDownloadSettings(downloadSettings) {
         network: normalizedNetwork || 'xhttp',
         ...(result.port != null ? { port: result.port } : {}),
         ...(result.security != null ? { security: result.security } : {}),
-        ...(result.tlsSettings != null ? { tlsSettings: result.tlsSettings } : {}),
+        ...(result.tlsSettings != null
+            ? { tlsSettings: result.tlsSettings }
+            : {}),
         ...(result.realitySettings != null
             ? { realitySettings: result.realitySettings }
             : {}),
-        ...(result.xhttpSettings != null ? { xhttpSettings: result.xhttpSettings } : {}),
+        ...(result.xhttpSettings != null
+            ? { xhttpSettings: result.xhttpSettings }
+            : {}),
     };
 }
 
@@ -316,6 +330,7 @@ function buildStructuredVlessExtraObject(proxy) {
 
     const downloadSettings = buildXhttpDownloadSettings(
         xhttpOpts['download-settings'],
+        xhttpOpts,
     );
     if (downloadSettings) {
         extra.downloadSettings = downloadSettings;