PM-199, PM-209 Denial of service fix

.circleci/config.yml

@@ -360,6 +360,7 @@ workflows:
                 - develop
                 - TOP-1390
                 - PM-191-2
+                - pm-199
       # This is alternate dev env for parallel testing
       # Deprecate this workflow due to beta env shutdown
       # https://topcoder.atlassian.net/browse/CORE-251

src/server/index.js

@@ -42,17 +42,48 @@ global.atob = atob;
 
 const CMS_BASE_URL = `https://app.contentful.com/spaces/${config.SECRET.CONTENTFUL.SPACE_ID}`;
 
-let ts = path.resolve(__dirname, '../../.build-info');
-ts = JSON.parse(fs.readFileSync(ts));
-ts = moment(ts.timestamp).valueOf();
+const getTimestamp = async () => {
+  let timestamp;
+  try {
+    const filePath = path.resolve(__dirname, '../../.build-info');
+    if (!filePath.startsWith(path.resolve(__dirname, '../../'))) {
+      throw new Error('Invalid file path detected');
+    }
+
+    const MAX_FILE_SIZE = 10 * 1024; // 10 KB max file size
+    const stats = await fs.promises.stat(filePath);
+    if (stats.size > MAX_FILE_SIZE) {
+      throw new Error('File is too large and may cause DoS issues');
+    }
+
+    const fileContent = await fs.promises.readFile(filePath, 'utf-8');
+
+    let tsData;
+    try {
+      tsData = JSON.parse(fileContent);
+    } catch (parseErr) {
+      throw new Error('Invalid JSON format in file');
+    }
+
+    if (!tsData || !tsData.timestamp) {
+      throw new Error('Timestamp is missing in the JSON file');
+    }
+
+    timestamp = moment(tsData.timestamp).valueOf();
+  } catch (err) {
+    console.error('Error:', err.message);
+  }
+
+  return timestamp;
+};
 
 const sw = `sw.js${process.env.NODE_ENV === 'production' ? '' : '?debug'}`;
 const swScope = '/challenges'; // we are currently only interested in improving challenges pages
 
 const tcoPattern = new RegExp(/^tco\d{2}\.topcoder(?:-dev)?\.com$/i);
 const universalNavUrl = config.UNIVERSAL_NAV_URL;
 
-const EXTRA_SCRIPTS = [
+const getExtraScripts = ts => [
   `<script type="application/javascript">
   if('serviceWorker' in navigator){
     navigator.serviceWorker.register('${swScope}/${sw}', {scope: '${swScope}'}).then(
@@ -112,9 +143,11 @@ async function beforeRender(req, suggestedConfig) {
 
   await DoSSR(req, store, Application);
 
+  const ts = await getTimestamp();
+
   return {
     configToInject: { ...suggestedConfig, EXCHANGE_RATES: rates },
-    extraScripts: EXTRA_SCRIPTS,
+    extraScripts: getExtraScripts(ts),
     store,
   };
 }

src/server/services/communities.js

@@ -30,24 +30,57 @@ async function getGroupsService() {
   return res;
 }
 
-const METADATA_PATH = path.resolve(__dirname, '../tc-communities');
-const VALID_IDS = isomorphy.isServerSide()
-&& fs.readdirSync(METADATA_PATH).filter((id) => {
-  /* Here we check which ids are correct, and also popuate SUBDOMAIN_COMMUNITY
-   * map. */
-  const uri = path.resolve(METADATA_PATH, id, 'metadata.json');
+const getValidIds = async (METADATA_PATH) => {
+  if (!isomorphy.isServerSide()) return [];
+  let VALID_IDS = [];
+
   try {
-    const meta = JSON.parse(fs.readFileSync(uri, 'utf8'));
-    if (meta.subdomains) {
-      meta.subdomains.forEach((subdomain) => {
-        SUBDOMAIN_COMMUNITY[subdomain] = id;
-      });
-    }
-    return true;
-  } catch (e) {
-    return false;
+    const ids = await fs.promises.readdir(METADATA_PATH);
+    const validationPromises = ids.map(async (id) => {
+      const uri = path.resolve(METADATA_PATH, id, 'metadata.json');
+
+      try {
+        // Check if the file exists
+        await fs.promises.access(uri);
+
+        // Get file stats
+        const stats = await fs.promises.stat(uri);
+        const MAX_FILE_SIZE = 1 * 1024 * 1024; // 1 MB
+        if (stats.size > MAX_FILE_SIZE) {
+          console.warn(`Metadata file too large for ID: ${id}`);
+          return null; // Exclude invalid ID
+        }
+
+        // Parse and validate JSON
+        const meta = JSON.parse(await fs.promises.readFile(uri, 'utf8'));
+
+        // Check if "subdomains" is a valid array
+        if (Array.isArray(meta.subdomains)) {
+          meta.subdomains.forEach((subdomain) => {
+            if (typeof subdomain === 'string') {
+              SUBDOMAIN_COMMUNITY[subdomain] = id;
+            } else {
+              console.warn(`Invalid subdomain entry for ID: ${id}`);
+            }
+          });
+        }
+
+        return id;
+      } catch (e) {
+        console.error(`Error processing metadata for ID: ${id}`, e.message);
+        return null;
+      }
+    });
+
+    const results = await Promise.all(validationPromises);
+    VALID_IDS = results.filter(id => id !== null);
+  } catch (err) {
+    console.error(`Error reading metadata directory: ${METADATA_PATH}`, err.message);
+    return [];
   }
-});
+
+  return VALID_IDS;
+};
 
 /**
  * Given an array of group IDs, returns an array containing IDs of all those
@@ -140,10 +173,12 @@ getMetadata.maxage = 5 * 60 * 1000; // 5 min in ms.
  * @return {Promise} Resolves to the array of community data objects. Each of
  *  the objects indludes only the most important data on the community.
  */
-export function getList(userGroupIds) {
+export async function getList(userGroupIds) {
   const list = [];
+  const METADATA_PATH = path.resolve(__dirname, '../tc-communities');
+  const validIds = await getValidIds(METADATA_PATH);
   return Promise.all(
-    VALID_IDS.map(id => getMetadata(id).then((data) => {
+    validIds.map(id => getMetadata(id).then((data) => {
       if (!data.authorizedGroupIds
           || _.intersection(data.authorizedGroupIds, userGroupIds).length) {
         list.push({