refactor: logic

Author: alexander-akait

lib/Server.js

@@ -307,6 +307,8 @@ function useFn(route, fn) {
   return /** @type {BasicApplication} */ ({});
 }
 
+const DEFAULT_ALLOWED_PROTOCOLS = /^(file|.+-extension):/i;
+
 /**
  * @typedef {Object} BasicApplication
  * @property {typeof useFn} use
@@ -1961,7 +1963,7 @@ class Server {
           (req.headers);
         const headerName = headers[":authority"] ? ":authority" : "host";
 
-        if (this.checkHeader(headers, headerName)) {
+        if (this.isValidHost(headers, headerName)) {
           next();
           return;
         }
@@ -2668,8 +2670,9 @@ class Server {
 
         if (
           !headers ||
-          !this.checkHeader(headers, "host") ||
-          !this.checkHeader(headers, "origin")
+          !this.isValidHost(headers, "host") ||
+          !this.isValidHost(headers, "origin") ||
+          !this.isSameOrigin(headers)
         ) {
           this.sendMessage([client], "error", "Invalid Host/Origin header");
 
@@ -3107,101 +3110,174 @@ class Server {
 
   /**
    * @private
-   * @param {{ [key: string]: string | undefined }} headers
-   * @param {string} headerToCheck
+   * @param {string} value
    * @returns {boolean}
    */
-  checkHeader(headers, headerToCheck) {
+  isHostAllowed(value) {
+    const { allowedHosts } = this.options;
+
     // allow user to opt out of this security check, at their own risk
     // by explicitly enabling allowedHosts
-    if (this.options.allowedHosts === "all") {
+    if (allowedHosts === "all") {
       return true;
     }
 
+    // always allow localhost host, for convenience
+    // allow if value is in allowedHosts
+    if (Array.isArray(allowedHosts) && allowedHosts.length > 0) {
+      for (let hostIdx = 0; hostIdx < allowedHosts.length; hostIdx++) {
+        /** @type {string} */
+        const allowedHost = allowedHosts[hostIdx];
+
+        if (allowedHost === value) {
+          return true;
+        }
+
+        // support "." as a subdomain wildcard
+        // e.g. ".example.com" will allow "example.com", "www.example.com", "subdomain.example.com", etc
+        if (allowedHost[0] === ".") {
+          // "example.com"  (value === allowedHost.substring(1))
+          // "*.example.com"  (value.endsWith(allowedHost))
+          if (
+            value === allowedHost.substring(1) ||
+            /** @type {string} */
+            (value).endsWith(allowedHost)
+          ) {
+            return true;
+          }
+        }
+      }
+    }
+
+    // Also allow if `client.webSocketURL.hostname` provided
+    if (
+      this.options.client &&
+      typeof (
+        /** @type {ClientConfiguration} */
+        (this.options.client).webSocketURL
+      ) !== "undefined"
+    ) {
+      return (
+        /** @type {WebSocketURL} */
+        (/** @type {ClientConfiguration} */ (this.options.client).webSocketURL)
+          .hostname === value
+      );
+    }
+
+    return false;
+  }
+
+  /**
+   * @private
+   * @param {{ [key: string]: string | undefined }} headers
+   * @param {string} headerToCheck
+   * @returns {boolean}
+   */
+  isValidHost(headers, headerToCheck) {
     // get the Host header and extract hostname
     // we don't care about port not matching
-    const hostHeader = headers[headerToCheck];
+    const header = headers[headerToCheck];
 
-    if (!hostHeader) {
+    if (!header) {
       return false;
     }
 
-    if (/^(file|.+-extension):/i.test(hostHeader)) {
+    if (DEFAULT_ALLOWED_PROTOCOLS.test(header)) {
       return true;
     }
 
     // use the node url-parser to retrieve the hostname from the host-header.
     const hostname = url.parse(
-      // if hostHeader doesn't have scheme, add // for parsing.
-      /^(.+:)?\/\//.test(hostHeader) ? hostHeader : `//${hostHeader}`,
+      // if header doesn't have scheme, add // for parsing.
+      /^(.+:)?\/\//.test(header) ? header : `//${header}`,
       false,
       true,
     ).hostname;
 
+    if (hostname === null) {
+      return false;
+    }
+
+    if (this.isHostAllowed(hostname)) {
+      return true;
+    }
+
     // always allow requests with explicit IPv4 or IPv6-address.
     // A note on IPv6 addresses:
-    // hostHeader will always contain the brackets denoting
+    // header will always contain the brackets denoting
     // an IPv6-address in URLs,
     // these are removed from the hostname in url.parse(),
     // so we have the pure IPv6-address in hostname.
     // For convenience, always allow localhost (hostname === 'localhost')
     // and its subdomains (hostname.endsWith(".localhost")).
     // allow hostname of listening address  (hostname === this.options.host)
     const isValidHostname =
-      (hostname !== null &&
-        (ipaddr.IPv4.isValid(hostname) || ipaddr.IPv6.isValid(hostname))) ||
+      ipaddr.IPv4.isValid(hostname) ||
+      ipaddr.IPv6.isValid(hostname) ||
       hostname === "localhost" ||
-      (hostname !== null && hostname.endsWith(".localhost")) ||
+      hostname.endsWith(".localhost") ||
       hostname === this.options.host;
 
     if (isValidHostname) {
       return true;
     }
 
-    const { allowedHosts } = this.options;
+    // disallow
+    return false;
+  }
 
-    // always allow localhost host, for convenience
-    // allow if hostname is in allowedHosts
-    if (Array.isArray(allowedHosts) && allowedHosts.length > 0) {
-      for (let hostIdx = 0; hostIdx < allowedHosts.length; hostIdx++) {
-        /** @type {string} */
-        const allowedHost = allowedHosts[hostIdx];
+  /**
+   * @private
+   * @param {{ [key: string]: string | undefined }} headers
+   * @returns {boolean}
+   */
+  isSameOrigin(headers) {
+    const originHeader = headers.origin;
 
-        if (allowedHost === hostname) {
-          return true;
-        }
+    if (!originHeader) {
+      return true;
+    }
 
-        // support "." as a subdomain wildcard
-        // e.g. ".example.com" will allow "example.com", "www.example.com", "subdomain.example.com", etc
-        if (allowedHost[0] === ".") {
-          // "example.com"  (hostname === allowedHost.substring(1))
-          // "*.example.com"  (hostname.endsWith(allowedHost))
-          if (
-            hostname === allowedHost.substring(1) ||
-            /** @type {string} */ (hostname).endsWith(allowedHost)
-          ) {
-            return true;
-          }
-        }
-      }
+    if (DEFAULT_ALLOWED_PROTOCOLS.test(originHeader)) {
+      return true;
     }
 
-    // Also allow if `client.webSocketURL.hostname` provided
-    if (
-      this.options.client &&
-      typeof (
-        /** @type {ClientConfiguration} */ (this.options.client).webSocketURL
-      ) !== "undefined"
-    ) {
-      return (
-        /** @type {WebSocketURL} */
-        (/** @type {ClientConfiguration} */ (this.options.client).webSocketURL)
-          .hostname === hostname
-      );
+    const origin = url.parse(originHeader, false, true).hostname;
+
+    if (origin === null) {
+      return false;
     }
 
-    // disallow
-    return false;
+    if (this.isHostAllowed(origin)) {
+      return true;
+    }
+
+    const hostHeader = headers.host;
+
+    if (!hostHeader) {
+      return false;
+    }
+
+    if (DEFAULT_ALLOWED_PROTOCOLS.test(hostHeader)) {
+      return true;
+    }
+
+    const host = url.parse(
+      // if hostHeader doesn't have scheme, add // for parsing.
+      /^(.+:)?\/\//.test(hostHeader) ? hostHeader : `//${hostHeader}`,
+      false,
+      true,
+    ).hostname;
+
+    if (host === null) {
+      return false;
+    }
+
+    if (this.isHostAllowed(host)) {
+      return true;
+    }
+
+    return origin === host;
   }
 
   /**

test/e2e/__snapshots__/allowed-hosts.test.js.snap.webpack5

@@ -62,6 +62,46 @@ exports[`allowed hosts should connect web socket client using "[::1] host to web
 
 exports[`allowed hosts should connect web socket client using "[::1] host to web socket server with the "auto" value ("ws"): page errors 1`] = `[]`;
 
+exports[`allowed hosts should connect web socket client using "0.0.0.0" host to web socket server with the "auto" value ("sockjs"): console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+]
+`;
+
+exports[`allowed hosts should connect web socket client using "0.0.0.0" host to web socket server with the "auto" value ("sockjs"): page errors 1`] = `[]`;
+
+exports[`allowed hosts should connect web socket client using "0.0.0.0" host to web socket server with the "auto" value ("ws"): console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+]
+`;
+
+exports[`allowed hosts should connect web socket client using "0.0.0.0" host to web socket server with the "auto" value ("ws"): page errors 1`] = `[]`;
+
+exports[`allowed hosts should connect web socket client using "127.0.0.1" host to web socket server by default ("sockjs"): console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+]
+`;
+
+exports[`allowed hosts should connect web socket client using "127.0.0.1" host to web socket server by default ("sockjs"): page errors 1`] = `[]`;
+
+exports[`allowed hosts should connect web socket client using "127.0.0.1" host to web socket server by default ("ws"): console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+]
+`;
+
+exports[`allowed hosts should connect web socket client using "127.0.0.1" host to web socket server by default ("ws"): page errors 1`] = `[]`;
+
 exports[`allowed hosts should connect web socket client using "127.0.0.1" host to web socket server with the "auto" value ("sockjs"): console messages 1`] = `
 [
   "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
@@ -122,6 +162,26 @@ exports[`allowed hosts should connect web socket client using "file:" protocol t
 
 exports[`allowed hosts should connect web socket client using "file:" protocol to web socket server with the "auto" value ("ws"): page errors 1`] = `[]`;
 
+exports[`allowed hosts should connect web socket client using "localhost" host to web socket server by default ("sockjs"): console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+]
+`;
+
+exports[`allowed hosts should connect web socket client using "localhost" host to web socket server by default ("sockjs"): page errors 1`] = `[]`;
+
+exports[`allowed hosts should connect web socket client using "localhost" host to web socket server by default ("ws"): console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+]
+`;
+
+exports[`allowed hosts should connect web socket client using "localhost" host to web socket server by default ("ws"): page errors 1`] = `[]`;
+
 exports[`allowed hosts should connect web socket client using custom hostname to web socket server with the "all" value ("sockjs"): console messages 1`] = `
 [
   "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
@@ -262,6 +322,26 @@ exports[`allowed hosts should connect web socket client using localhost to web s
 
 exports[`allowed hosts should connect web socket client using localhost to web socket server with the "auto" value ("ws"): page errors 1`] = `[]`;
 
+exports[`allowed hosts should connect web socket client using origin header containing an IP address with the custom hostname value ("sockjs"): (work) console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+]
+`;
+
+exports[`allowed hosts should connect web socket client using origin header containing an IP address with the custom hostname value ("sockjs"): (work) page errors 1`] = `[]`;
+
+exports[`allowed hosts should connect web socket client using origin header containing an IP address with the custom hostname value ("ws"): (work) console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+]
+`;
+
+exports[`allowed hosts should connect web socket client using origin header containing an IP address with the custom hostname value ("ws"): (work) page errors 1`] = `[]`;
+
 exports[`allowed hosts should disconnect web client using localhost to web socket server with the "auto" value ("sockjs"): console messages 1`] = `
 [
   "Failed to load resource: the server responded with a status of 403 (Forbidden)",
@@ -282,6 +362,32 @@ exports[`allowed hosts should disconnect web client using localhost to web socke
 
 exports[`allowed hosts should disconnect web client using localhost to web socket server with the "auto" value ("ws"): page errors 1`] = `[]`;
 
+exports[`allowed hosts should disconnect web client using origin header containing an IP address with the "auto" value ("sockjs"): (work) console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+  "[webpack-dev-server] Invalid Host/Origin header",
+  "[webpack-dev-server] Disconnected!",
+  "[webpack-dev-server] Trying to reconnect...",
+]
+`;
+
+exports[`allowed hosts should disconnect web client using origin header containing an IP address with the "auto" value ("sockjs"): (work) page errors 1`] = `[]`;
+
+exports[`allowed hosts should disconnect web client using origin header containing an IP address with the "auto" value ("ws"): (work) console messages 1`] = `
+[
+  "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",
+  "[HMR] Waiting for update signal from WDS...",
+  "Hey.",
+  "[webpack-dev-server] Invalid Host/Origin header",
+  "[webpack-dev-server] Disconnected!",
+  "[webpack-dev-server] Trying to reconnect...",
+]
+`;
+
+exports[`allowed hosts should disconnect web client using origin header containing an IP address with the "auto" value ("ws"): (work) page errors 1`] = `[]`;
+
 exports[`allowed hosts should disconnect web socket client using custom hostname from web socket server with the "auto" value based on the "host" header ("sockjs"): console messages 1`] = `
 [
   "[webpack-dev-server] Server started: Hot Module Replacement enabled, Live Reloading enabled, Progress disabled, Overlay enabled.",