fix: harden cliproxy usage cache

src/web-server/usage/cliproxy-usage-syncer.ts

@@ -50,6 +50,8 @@ const HISTORY_RETENTION_DAYS = Math.max(
 );
 const HISTORY_RETENTION_MS = HISTORY_RETENTION_DAYS * 24 * 60 * 60 * 1000;
 const MAX_WRITE_ATTEMPTS = 3;
+const PRIVATE_DIR_MODE = 0o700;
+const PRIVATE_FILE_MODE = 0o600;
 
 /** Sync interval in ms, configurable via CCS_CLIPROXY_SYNC_INTERVAL env var (default: 5 min) */
 const SYNC_INTERVAL_MS = Math.max(
@@ -68,11 +70,19 @@ function getLatestSnapshotPath(): string {
   return path.join(getCliproxyCacheDir(), 'latest.json');
 }
 
+function ensurePrivateDirectory(dir: string): void {
+  fs.mkdirSync(dir, { recursive: true, mode: PRIVATE_DIR_MODE });
+  fs.chmodSync(dir, PRIVATE_DIR_MODE);
+}
+
 function ensureCliproxyCacheDir(): void {
-  const dir = getCliproxyCacheDir();
-  if (!fs.existsSync(dir)) {
-    fs.mkdirSync(dir, { recursive: true });
-  }
+  const ccsDir = getCcsDir();
+  const cacheDir = path.join(ccsDir, 'cache');
+  const cliproxyCacheDir = path.join(cacheDir, 'cliproxy-usage');
+
+  ensurePrivateDirectory(ccsDir);
+  ensurePrivateDirectory(cacheDir);
+  ensurePrivateDirectory(cliproxyCacheDir);
 }
 
 function getSnapshotTimestamp(): number {
@@ -112,8 +122,6 @@ function buildLegacyHistoryDetails(
       details.push({
         model: breakdown.modelName,
         timestamp: buildHourlyTimestamp(hour.hour),
-        source: hour.source,
-        authIndex: 'legacy-hourly',
         inputTokens: breakdown.inputTokens,
         outputTokens: breakdown.outputTokens,
         cacheReadTokens: breakdown.cacheReadTokens,
@@ -135,8 +143,6 @@ function buildLegacyHistoryDetails(
       details.push({
         model: breakdown.modelName,
         timestamp: buildDailyTimestamp(day.date),
-        source: day.source,
-        authIndex: 'legacy-daily',
         inputTokens: breakdown.inputTokens,
         outputTokens: breakdown.outputTokens,
         cacheReadTokens: breakdown.cacheReadTokens,
@@ -255,7 +261,11 @@ async function writeSnapshotWithMerge(
     const snapshot = buildSnapshot(baseSnapshot?.details ?? [], incomingDetails);
     const tempFile = `${snapshotPath}.${process.pid}.${snapshot.timestamp}.tmp`;
 
-    fs.writeFileSync(tempFile, JSON.stringify(snapshot), 'utf-8');
+    fs.writeFileSync(tempFile, JSON.stringify(snapshot), {
+      encoding: 'utf-8',
+      mode: PRIVATE_FILE_MODE,
+    });
+    fs.chmodSync(tempFile, PRIVATE_FILE_MODE);
 
     const latestSnapshot = readSnapshot(false);
     const latestTimestamp = latestSnapshot?.timestamp ?? -Infinity;
@@ -265,6 +275,7 @@ async function writeSnapshotWithMerge(
     }
 
     fs.renameSync(tempFile, snapshotPath);
+    fs.chmodSync(snapshotPath, PRIVATE_FILE_MODE);
     console.log(ok('CLIProxy usage snapshot updated'));
     return;
   }

src/web-server/usage/cliproxy-usage-transformer.ts

@@ -22,8 +22,6 @@ export interface CliproxyUsageHistoryDetail {
   model: string;
   provider?: string;
   timestamp: string;
-  source: string;
-  authIndex: string;
   inputTokens: number;
   outputTokens: number;
   cacheReadTokens: number;
@@ -68,8 +66,6 @@ function createHistoryDetail(
     model,
     provider: pricingProvider,
     timestamp: detail.timestamp,
-    source: detail.source,
-    authIndex: String(detail.auth_index),
     inputTokens: detail.tokens?.input_tokens ?? 0,
     outputTokens: detail.tokens?.output_tokens ?? 0,
     cacheReadTokens: detail.tokens?.cached_tokens ?? 0,
@@ -128,13 +124,25 @@ export function extractCliproxyUsageHistoryDetails(
   return results;
 }
 
+function sanitizeHistoryDetail(detail: CliproxyUsageHistoryDetail): CliproxyUsageHistoryDetail {
+  return {
+    model: detail.model,
+    ...(detail.provider && { provider: detail.provider }),
+    timestamp: detail.timestamp,
+    inputTokens: detail.inputTokens,
+    outputTokens: detail.outputTokens,
+    cacheReadTokens: detail.cacheReadTokens,
+    requestCount: detail.requestCount,
+    cost: detail.cost,
+    failed: detail.failed,
+  };
+}
+
 function createHistorySignature(detail: CliproxyUsageHistoryDetail): string {
   return [
     detail.model,
     detail.provider ?? '',
     detail.timestamp,
-    detail.source,
-    detail.authIndex,
     detail.inputTokens,
     detail.outputTokens,
     detail.cacheReadTokens,
@@ -182,7 +190,7 @@ export function mergeCliproxyUsageHistoryDetails(
   const merged: CliproxyUsageHistoryDetail[] = [];
   for (const { detail, count } of existingCounts.values()) {
     for (let index = 0; index < count; index++) {
-      merged.push({ ...detail });
+      merged.push(sanitizeHistoryDetail(detail));
     }
   }
 

tests/unit/web-server/cliproxy-usage-syncer.test.ts

@@ -109,6 +109,21 @@ describe('cliproxy usage syncer', () => {
     const snapshotPath = path.join(ccsDir, 'cache', 'cliproxy-usage', 'latest.json');
     expect(fs.existsSync(snapshotPath)).toBe(true);
 
+    const snapshot = JSON.parse(fs.readFileSync(snapshotPath, 'utf-8')) as {
+      details: Array<Record<string, unknown>>;
+    };
+    expect(snapshot.details[0]).not.toHaveProperty('source');
+    expect(snapshot.details[0]).not.toHaveProperty('authIndex');
+
+    if (process.platform !== 'win32') {
+      const cacheDir = path.join(ccsDir, 'cache');
+      const cliproxyCacheDir = path.dirname(snapshotPath);
+      expect(fs.statSync(ccsDir).mode & 0o777).toBe(0o700);
+      expect(fs.statSync(cacheDir).mode & 0o777).toBe(0o700);
+      expect(fs.statSync(cliproxyCacheDir).mode & 0o777).toBe(0o700);
+      expect(fs.statSync(snapshotPath).mode & 0o777).toBe(0o600);
+    }
+
     const cached = await runWithScopedConfigDir(ccsDir, async () => {
       return await loadCachedCliproxyData();
     });

tests/unit/web-server/cliproxy-usage-transformer.test.ts

@@ -109,6 +109,8 @@ describe('cliproxy usage transformer', () => {
     const flat = extractCliproxyUsageHistoryDetails(sampleResponse);
     expect(flat).toHaveLength(4);
     expect(flat[0].provider).toBe('google');
+    expect(flat[0]).not.toHaveProperty('source');
+    expect(flat[0]).not.toHaveProperty('authIndex');
     expect(
       flat.some(
         (entry) =>
@@ -134,6 +136,19 @@ describe('cliproxy usage transformer', () => {
     expect(merged).toHaveLength(details.length);
   });
 
+  it('strips legacy account identifiers when merging persisted history', () => {
+    const details = extractCliproxyUsageHistoryDetails(sampleResponse);
+    const legacyDetail = {
+      ...details[0],
+      source: 'user@example.com',
+      authIndex: 'auth-file-7',
+    };
+    const merged = mergeCliproxyUsageHistoryDetails([legacyDetail], []);
+
+    expect(merged[0]).not.toHaveProperty('source');
+    expect(merged[0]).not.toHaveProperty('authIndex');
+  });
+
   it('preserves legitimate duplicate requests when the incoming batch has more occurrences', () => {
     const details = extractCliproxyUsageHistoryDetails(sampleResponse);
     const repeated = [details[0], { ...details[0] }];