fix(auth): prevent unexpected session logout

src/services/auth.ts

@@ -1,5 +1,6 @@
 import { Env, JWTPayload, User } from '../types';
 import { verifyJWT, createJWT, createRefreshToken } from '../utils/jwt';
+import { getRefreshTokenSlidingTtlMs, LIMITS } from '../config/limits';
 import { StorageService } from './storage';
 
 // Server-side iterations for second-layer hashing.
@@ -28,11 +29,12 @@ export type RefreshAccessTokenFailureReason =
   | 'token_not_found_or_expired'
   | 'user_missing'
   | 'user_inactive'
+  | 'security_stamp_mismatch'
   | 'device_missing'
   | 'device_session_mismatch';
 
 export type RefreshAccessTokenResult =
-  | { ok: true; accessToken: string; user: User; device: { identifier: string; sessionStamp: string } | null }
+  | { ok: true; accessToken: string; user: User; device: { identifier: string; sessionStamp: string } | null; expiresAt: number }
   | {
       ok: false;
       reason: RefreshAccessTokenFailureReason;
@@ -190,9 +192,23 @@ export class AuthService {
   }
 
   // Generate refresh token
-  async generateRefreshToken(userId: string, device?: { identifier: string; sessionStamp: string } | null): Promise<string> {
+  async generateRefreshToken(
+    user: User,
+    device?: { identifier: string; sessionStamp: string } | null,
+    clientType: string = 'other'
+  ): Promise<string> {
     const token = createRefreshToken();
-    await this.storage.saveRefreshToken(token, userId, undefined, device?.identifier ?? null, device?.sessionStamp ?? null);
+    const now = Date.now();
+    await this.storage.saveRefreshToken(
+      token,
+      user.id,
+      now + getRefreshTokenSlidingTtlMs(clientType),
+      device?.identifier ?? null,
+      device?.sessionStamp ?? null,
+      user.securityStamp,
+      clientType,
+      now + LIMITS.auth.refreshTokenAbsoluteTtlMs
+    );
     return token;
   }
 
@@ -251,25 +267,42 @@ export class AuthService {
       return { ok: false, reason: 'user_inactive', userId: user.id, deviceIdentifier: record.deviceIdentifier };
     }
 
+    if (record.securityStamp && record.securityStamp !== user.securityStamp) {
+      await this.storage.deleteRefreshToken(refreshToken);
+      return { ok: false, reason: 'security_stamp_mismatch', userId: user.id, deviceIdentifier: record.deviceIdentifier };
+    }
+    if (!record.securityStamp) {
+      await this.storage.bindRefreshTokenSecurityStamp(refreshToken, user.securityStamp);
+    }
+
     let device: { identifier: string; sessionStamp: string } | null = null;
-    if (!record.deviceIdentifier || !record.deviceSessionStamp) {
-      await this.storage.deleteRefreshToken(refreshToken);
-      return { ok: false, reason: 'device_missing', userId: user.id, deviceIdentifier: record.deviceIdentifier };
+    if (record.deviceIdentifier) {
+      const boundDevice = await this.storage.getDevice(user.id, record.deviceIdentifier);
+      if (!boundDevice) {
+        await this.storage.deleteRefreshToken(refreshToken);
+        return { ok: false, reason: 'device_missing', userId: user.id, deviceIdentifier: record.deviceIdentifier };
+      }
+      if (record.deviceSessionStamp && boundDevice.sessionStamp !== record.deviceSessionStamp) {
+        await this.storage.deleteRefreshToken(refreshToken);
+        return { ok: false, reason: 'device_session_mismatch', userId: user.id, deviceIdentifier: record.deviceIdentifier };
+      }
+      if (!record.deviceSessionStamp) {
+        await this.storage.bindRefreshTokenDeviceStamp(refreshToken, boundDevice.sessionStamp);
+      }
+      device = { identifier: boundDevice.deviceIdentifier, sessionStamp: boundDevice.sessionStamp };
     }
 
-    const boundDevice = await this.storage.getDevice(user.id, record.deviceIdentifier);
-    if (!boundDevice) {
-      await this.storage.deleteRefreshToken(refreshToken);
-      return { ok: false, reason: 'device_missing', userId: user.id, deviceIdentifier: record.deviceIdentifier };
+    const now = Date.now();
+    const expiresAt = Math.min(
+      now + getRefreshTokenSlidingTtlMs(record.clientType),
+      record.absoluteExpiresAt || (now + LIMITS.auth.refreshTokenAbsoluteTtlMs)
+    );
+    const extended = await this.storage.extendRefreshTokenExpiry(refreshToken, expiresAt, now);
+    if (!extended) {
+      return { ok: false, reason: 'token_not_found_or_expired', userId: user.id, deviceIdentifier: record.deviceIdentifier };
     }
-    if (boundDevice.sessionStamp !== record.deviceSessionStamp) {
-      await this.storage.deleteRefreshToken(refreshToken);
-      return { ok: false, reason: 'device_session_mismatch', userId: user.id, deviceIdentifier: record.deviceIdentifier };
-    }
-    device = { identifier: boundDevice.deviceIdentifier, sessionStamp: boundDevice.sessionStamp };
-
     const accessToken = await this.generateAccessToken(user, device);
-    return { ok: true, accessToken, user, device };
+    return { ok: true, accessToken, user, device, expiresAt };
   }
 
   async refreshAccessToken(

src/services/storage-device-repo.ts

@@ -45,7 +45,8 @@ export async function upsertDevice(
   await db
     .prepare(
       'INSERT INTO devices(user_id, device_identifier, name, type, session_stamp, encrypted_user_key, encrypted_public_key, encrypted_private_key, push_uuid, banned, banned_at, device_note, last_seen_at, created_at, updated_at) VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, 0, NULL, ?, ?, ?, ?) ' +
-        'ON CONFLICT(user_id, device_identifier) DO UPDATE SET name=excluded.name, type=excluded.type, session_stamp=excluded.session_stamp, ' +
+        'ON CONFLICT(user_id, device_identifier) DO UPDATE SET name=excluded.name, type=excluded.type, ' +
+        'session_stamp=CASE WHEN devices.session_stamp IS NULL OR devices.session_stamp = ? THEN excluded.session_stamp ELSE devices.session_stamp END, ' +
         'encrypted_user_key=COALESCE(excluded.encrypted_user_key, encrypted_user_key), ' +
         'encrypted_public_key=COALESCE(excluded.encrypted_public_key, encrypted_public_key), ' +
         'encrypted_private_key=COALESCE(excluded.encrypted_private_key, encrypted_private_key), ' +
@@ -66,7 +67,8 @@ export async function upsertDevice(
       existingDevice?.deviceNote ?? null,
       now,
       now,
-      now
+      now,
+      ''
     )
     .run();
 }

src/services/storage-refresh-token-repo.ts

@@ -11,16 +11,34 @@ export async function saveRefreshToken(
   userId: string,
   expiresAtMs: number,
   deviceIdentifier?: string | null,
-  deviceSessionStamp?: string | null
+  deviceSessionStamp?: string | null,
+  securityStamp?: string | null,
+  clientType?: string | null,
+  absoluteExpiresAtMs?: number | null
 ): Promise<void> {
   await maybeCleanupExpiredRefreshTokens(Date.now());
   const tokenKey = await refreshTokenKey(token);
+  const now = Date.now();
   await db
     .prepare(
-      'INSERT INTO refresh_tokens(token, user_id, expires_at, device_identifier, device_session_stamp) VALUES(?, ?, ?, ?, ?) ' +
-        'ON CONFLICT(token) DO UPDATE SET user_id=excluded.user_id, expires_at=excluded.expires_at, device_identifier=excluded.device_identifier, device_session_stamp=excluded.device_session_stamp'
+      'INSERT INTO refresh_tokens(token, user_id, expires_at, device_identifier, device_session_stamp, security_stamp, created_at, last_used_at, absolute_expires_at, client_type) ' +
+        'VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?) ' +
+        'ON CONFLICT(token) DO UPDATE SET user_id=excluded.user_id, expires_at=excluded.expires_at, device_identifier=excluded.device_identifier, ' +
+        'device_session_stamp=excluded.device_session_stamp, security_stamp=excluded.security_stamp, last_used_at=excluded.last_used_at, ' +
+        'absolute_expires_at=excluded.absolute_expires_at, client_type=excluded.client_type'
+    )
+    .bind(
+      tokenKey,
+      userId,
+      expiresAtMs,
+      deviceIdentifier ?? null,
+      deviceSessionStamp ?? null,
+      securityStamp ?? null,
+      now,
+      now,
+      absoluteExpiresAtMs ?? null,
+      clientType ?? null
     )
-    .bind(tokenKey, userId, expiresAtMs, deviceIdentifier ?? null, deviceSessionStamp ?? null)
     .run();
 }
 
@@ -36,12 +54,25 @@ export async function getRefreshTokenRecord(
   const tokenKey = await refreshTokenKey(token);
 
   const row = await db
-    .prepare('SELECT user_id, expires_at, device_identifier, device_session_stamp FROM refresh_tokens WHERE token = ?')
+    .prepare(
+      'SELECT user_id, expires_at, device_identifier, device_session_stamp, security_stamp, created_at, last_used_at, absolute_expires_at, client_type ' +
+        'FROM refresh_tokens WHERE token = ?'
+    )
     .bind(tokenKey)
-    .first<{ user_id: string; expires_at: number; device_identifier: string | null; device_session_stamp: string | null }>();
+    .first<{
+      user_id: string;
+      expires_at: number;
+      device_identifier: string | null;
+      device_session_stamp: string | null;
+      security_stamp: string | null;
+      created_at: number | null;
+      last_used_at: number | null;
+      absolute_expires_at: number | null;
+      client_type: string | null;
+    }>();
 
   if (!row) return null;
-  if (row.expires_at && row.expires_at < now) {
+  if ((row.expires_at && row.expires_at < now) || (row.absolute_expires_at && row.absolute_expires_at < now)) {
     await deleteRefreshTokenRecord(token);
     return null;
   }
@@ -50,9 +81,62 @@ export async function getRefreshTokenRecord(
     expiresAt: row.expires_at,
     deviceIdentifier: row.device_identifier ?? null,
     deviceSessionStamp: row.device_session_stamp ?? null,
+    securityStamp: row.security_stamp ?? null,
+    createdAt: row.created_at ?? null,
+    lastUsedAt: row.last_used_at ?? null,
+    absoluteExpiresAt: row.absolute_expires_at ?? null,
+    clientType: row.client_type ?? null,
   };
 }
 
+export async function extendRefreshTokenExpiry(
+  db: D1Database,
+  refreshTokenKey: RefreshTokenKeyFn,
+  token: string,
+  requestedExpiresAtMs: number,
+  nowMs: number
+): Promise<boolean> {
+  const tokenKey = await refreshTokenKey(token);
+  const result = await db
+    .prepare(
+      'UPDATE refresh_tokens SET ' +
+        'expires_at = CASE ' +
+        'WHEN absolute_expires_at IS NOT NULL AND absolute_expires_at < ? THEN absolute_expires_at ' +
+        'ELSE ? END, ' +
+        'last_used_at = ? ' +
+        'WHERE token = ? AND expires_at >= ? AND (absolute_expires_at IS NULL OR absolute_expires_at >= ?)'
+    )
+    .bind(requestedExpiresAtMs, requestedExpiresAtMs, nowMs, tokenKey, nowMs, nowMs)
+    .run();
+  return Number(result.meta.changes ?? 0) > 0;
+}
+
+export async function bindRefreshTokenSecurityStamp(
+  db: D1Database,
+  refreshTokenKey: RefreshTokenKeyFn,
+  token: string,
+  securityStamp: string
+): Promise<void> {
+  const tokenKey = await refreshTokenKey(token);
+  await db
+    .prepare('UPDATE refresh_tokens SET security_stamp = ? WHERE token = ? AND (security_stamp IS NULL OR security_stamp = ?)')
+    .bind(securityStamp, tokenKey, '')
+    .run();
+}
+
+export async function bindRefreshTokenDeviceStamp(
+  db: D1Database,
+  refreshTokenKey: RefreshTokenKeyFn,
+  token: string,
+  deviceSessionStamp: string
+): Promise<void> {
+  const tokenKey = await refreshTokenKey(token);
+  await db
+    .prepare('UPDATE refresh_tokens SET device_session_stamp = ? WHERE token = ? AND (device_session_stamp IS NULL OR device_session_stamp = ?)')
+    .bind(deviceSessionStamp, tokenKey, '')
+    .run();
+}
+
 export async function deleteRefreshToken(db: D1Database, refreshTokenKey: RefreshTokenKeyFn, token: string): Promise<void> {
   const tokenKey = await refreshTokenKey(token);
   await db.prepare('DELETE FROM refresh_tokens WHERE token = ?').bind(token).run();
@@ -71,30 +155,3 @@ export async function deleteRefreshTokensByDevice(db: D1Database, userId: string
     .run();
   return Number(result.meta.changes ?? 0);
 }
-
-export async function constrainRefreshTokenExpiry(
-  db: D1Database,
-  refreshTokenKey: RefreshTokenKeyFn,
-  token: string,
-  maxExpiresAtMs: number
-): Promise<void> {
-  const tokenKey = await refreshTokenKey(token);
-
-  await db
-    .prepare(
-      'UPDATE refresh_tokens ' +
-        'SET expires_at = CASE WHEN expires_at > ? THEN ? ELSE expires_at END ' +
-        'WHERE token = ?'
-    )
-    .bind(maxExpiresAtMs, maxExpiresAtMs, tokenKey)
-    .run();
-
-  await db
-    .prepare(
-      'UPDATE refresh_tokens ' +
-        'SET expires_at = CASE WHEN expires_at > ? THEN ? ELSE expires_at END ' +
-        'WHERE token = ?'
-    )
-    .bind(maxExpiresAtMs, maxExpiresAtMs, token)
-    .run();
-}

src/services/storage-schema.ts

@@ -74,11 +74,20 @@ const SCHEMA_STATEMENTS: readonly string[] = [
   'ALTER TABLE sends ADD COLUMN emails TEXT',
 
   'CREATE TABLE IF NOT EXISTS refresh_tokens (' +
-  'token TEXT PRIMARY KEY, user_id TEXT NOT NULL, expires_at INTEGER NOT NULL, device_identifier TEXT, device_session_stamp TEXT, ' +
+  'token TEXT PRIMARY KEY, user_id TEXT NOT NULL, expires_at INTEGER NOT NULL, device_identifier TEXT, device_session_stamp TEXT, security_stamp TEXT, created_at INTEGER, last_used_at INTEGER, absolute_expires_at INTEGER, client_type TEXT, ' +
   'FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE)',
   'CREATE INDEX IF NOT EXISTS idx_refresh_tokens_user ON refresh_tokens(user_id)',
   'ALTER TABLE refresh_tokens ADD COLUMN device_identifier TEXT',
   'ALTER TABLE refresh_tokens ADD COLUMN device_session_stamp TEXT',
+  'ALTER TABLE refresh_tokens ADD COLUMN security_stamp TEXT',
+  'ALTER TABLE refresh_tokens ADD COLUMN created_at INTEGER',
+  'ALTER TABLE refresh_tokens ADD COLUMN last_used_at INTEGER',
+  'ALTER TABLE refresh_tokens ADD COLUMN absolute_expires_at INTEGER',
+  'ALTER TABLE refresh_tokens ADD COLUMN client_type TEXT',
+  "UPDATE refresh_tokens SET security_stamp = (SELECT users.security_stamp FROM users WHERE users.id = refresh_tokens.user_id) WHERE security_stamp IS NULL OR security_stamp = ''",
+  "UPDATE refresh_tokens SET created_at = CAST(strftime('%s','now') AS INTEGER) * 1000 WHERE created_at IS NULL",
+  "UPDATE refresh_tokens SET last_used_at = created_at WHERE last_used_at IS NULL",
+  'UPDATE refresh_tokens SET absolute_expires_at = expires_at WHERE absolute_expires_at IS NULL',
 
   'CREATE TABLE IF NOT EXISTS invites (' +
   'code TEXT PRIMARY KEY, created_by TEXT NOT NULL, used_by TEXT, expires_at TEXT NOT NULL, status TEXT NOT NULL, created_at TEXT NOT NULL, updated_at TEXT NOT NULL, ' +
@@ -118,6 +127,8 @@ const SCHEMA_STATEMENTS: readonly string[] = [
   'ALTER TABLE devices ADD COLUMN last_seen_at TEXT',
   'CREATE INDEX IF NOT EXISTS idx_devices_user_last_seen ON devices(user_id, last_seen_at)',
   'CREATE INDEX IF NOT EXISTS idx_devices_user_push ON devices(user_id, push_token)',
+  "UPDATE refresh_tokens SET device_session_stamp = (SELECT devices.session_stamp FROM devices WHERE devices.user_id = refresh_tokens.user_id AND devices.device_identifier = refresh_tokens.device_identifier) WHERE device_identifier IS NOT NULL AND (device_session_stamp IS NULL OR device_session_stamp = '') AND EXISTS (SELECT 1 FROM devices WHERE devices.user_id = refresh_tokens.user_id AND devices.device_identifier = refresh_tokens.device_identifier)",
+  "UPDATE refresh_tokens SET client_type = CASE WHEN EXISTS (SELECT 1 FROM devices WHERE devices.user_id = refresh_tokens.user_id AND devices.device_identifier = refresh_tokens.device_identifier AND devices.type IN (0, 1)) THEN 'mobile' WHEN EXISTS (SELECT 1 FROM devices WHERE devices.user_id = refresh_tokens.user_id AND devices.device_identifier = refresh_tokens.device_identifier AND devices.type = 14) THEN 'web' ELSE 'other' END WHERE client_type IS NULL OR client_type = ''",
 
   'CREATE TABLE IF NOT EXISTS auth_requests (' +
   'id TEXT PRIMARY KEY, user_id TEXT NOT NULL, organization_id TEXT, type INTEGER NOT NULL, request_device_identifier TEXT NOT NULL, request_device_type INTEGER NOT NULL, ' +

src/services/storage.ts

@@ -87,10 +87,12 @@ import {
   saveSend as saveStoredSend,
 } from './storage-send-repo';
 import {
-  constrainRefreshTokenExpiry as constrainStoredRefreshTokenExpiry,
+  bindRefreshTokenDeviceStamp as bindStoredRefreshTokenDeviceStamp,
+  bindRefreshTokenSecurityStamp as bindStoredRefreshTokenSecurityStamp,
   deleteRefreshToken as deleteStoredRefreshToken,
   deleteRefreshTokensByDevice as deleteStoredRefreshTokensByDevice,
   deleteRefreshTokensByUserId as deleteStoredRefreshTokensByUserId,
+  extendRefreshTokenExpiry as extendStoredRefreshTokenExpiry,
   getRefreshTokenRecord as findStoredRefreshTokenRecord,
   saveRefreshToken as saveStoredRefreshToken,
 } from './storage-refresh-token-repo';
@@ -162,7 +164,7 @@ const STORAGE_SCHEMA_VERSION_KEY = 'schema.version';
 // Bump this whenever src/services/storage-schema.ts or migrations/0001_init.sql
 // changes. Existing D1 installs only rerun ensureStorageSchema() when this value
 // differs from config.schema.version.
-const STORAGE_SCHEMA_VERSION = '2026-07-05-passkey-2fa';
+const STORAGE_SCHEMA_VERSION = '2026-07-13-refresh-session-reuse';
 const REQUIRED_SCHEMA_TABLES = ['webauthn_credentials', 'webauthn_challenges', 'auth_requests', 'totp_login_replays'] as const;
 
 // D1-backed storage.
@@ -632,9 +634,13 @@ export class StorageService {
     userId: string,
     expiresAtMs?: number,
     deviceIdentifier?: string | null,
-    deviceSessionStamp?: string | null
+    deviceSessionStamp?: string | null,
+    securityStamp?: string | null,
+    clientType?: string | null,
+    absoluteExpiresAtMs?: number | null
   ): Promise<void> {
-    const expiresAt = expiresAtMs ?? (Date.now() + LIMITS.auth.refreshTokenTtlMs);
+    const now = Date.now();
+    const expiresAt = expiresAtMs ?? (now + LIMITS.auth.refreshTokenDefaultSlidingTtlMs);
     await saveStoredRefreshToken(
       this.db,
       this.refreshTokenKey.bind(this),
@@ -643,7 +649,10 @@ export class StorageService {
       userId,
       expiresAt,
       deviceIdentifier,
-      deviceSessionStamp
+      deviceSessionStamp,
+      securityStamp,
+      clientType,
+      absoluteExpiresAtMs ?? (now + LIMITS.auth.refreshTokenAbsoluteTtlMs)
     );
   }
 
@@ -717,11 +726,16 @@ export class StorageService {
     return deleteStoredRefreshTokensByDevice(this.db, userId, deviceIdentifier);
   }
 
-  // Keep a short overlap window for rotated refresh token to reduce
-  // multi-context refresh races (e.g. browser extension popup/background).
-  // Expiry is only tightened, never extended.
-  async constrainRefreshTokenExpiry(token: string, maxExpiresAtMs: number): Promise<void> {
-    await constrainStoredRefreshTokenExpiry(this.db, this.refreshTokenKey.bind(this), token, maxExpiresAtMs);
+  async extendRefreshTokenExpiry(token: string, requestedExpiresAtMs: number, nowMs: number = Date.now()): Promise<boolean> {
+    return extendStoredRefreshTokenExpiry(this.db, this.refreshTokenKey.bind(this), token, requestedExpiresAtMs, nowMs);
+  }
+
+  async bindRefreshTokenSecurityStamp(token: string, securityStamp: string): Promise<void> {
+    await bindStoredRefreshTokenSecurityStamp(this.db, this.refreshTokenKey.bind(this), token, securityStamp);
+  }
+
+  async bindRefreshTokenDeviceStamp(token: string, deviceSessionStamp: string): Promise<void> {
+    await bindStoredRefreshTokenDeviceStamp(this.db, this.refreshTokenKey.bind(this), token, deviceSessionStamp);
   }
 
   private async trustedTwoFactorTokenKey(token: string): Promise<string> {