Account for server vs host clock skew in cookie expiration times.

net/cookies/canonical_cookie.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Portions of this code based on Mozilla:
 //   (netwerk/cookie/src/nsCookieService.cpp)
 /* ***** BEGIN LICENSE BLOCK *****
  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
  *
  * The contents of this file are subject to the Mozilla Public License Version
@@ skipping 121 matching lines @@
       name_(pc.Name()),
       value_(pc.Value()),
       path_(CanonPath(url, pc)),
       mac_key_(pc.MACKey()),
       mac_algorithm_(pc.MACAlgorithm()),
       creation_date_(Time::Now()),
       last_access_date_(Time()),
       secure_(pc.IsSecure()),
       httponly_(pc.IsHttpOnly()) {
   if (pc.HasExpires())
-    expiry_date_ = CanonExpiration(pc, creation_date_);
+    expiry_date_ = CanonExpiration(pc, creation_date_, creation_date_);
 
   // Do the best we can with the domain.
   std::string cookie_domain;
   std::string domain_string;
   if (pc.HasDomain()) {
     domain_string = pc.Domain();
   }
   bool result
       = cookie_util::GetCookieDomainWithString(url, domain_string,
                                                 &cookie_domain);
@@ skipping 21 matching lines @@
 std::string CanonicalCookie::CanonPath(const GURL& url,
                                        const ParsedCookie& pc) {
   std::string path_string;
   if (pc.HasPath())
     path_string = pc.Path();
   return CanonPathWithString(url, path_string);
 }
 
 // static
 Time CanonicalCookie::CanonExpiration(const ParsedCookie& pc,
-                                      const Time& current) {
+                                      const Time& current,
+                                      const Time& server_time) {
   // First, try the Max-Age attribute.
   uint64 max_age = 0;
   if (pc.HasMaxAge() &&
 #ifdef COMPILER_MSVC
       sscanf_s(
 #else
       sscanf(
 #endif
              pc.MaxAge().c_str(), " %" PRIu64, &max_age) == 1) {
     return current + TimeDelta::FromSeconds(max_age);
   }
 
   // Try the Expires attribute.
-  if (pc.HasExpires())
-    return cookie_util::ParseCookieTime(pc.Expires());
+  if (pc.HasExpires()) {
+    // Adjust for clock skew between server and host.
+    return current + (cookie_util::ParseCookieTime(pc.Expires()) - server_time);
+  }
 
   // Invalid or no expiration, persistent cookie.
   return Time();
 }
 
 CanonicalCookie* CanonicalCookie::Create(const GURL& url,
                                          const ParsedCookie& pc) {
   if (!pc.IsValid()) {
     return NULL;
   }
@@ skipping 140 matching lines @@
 std::string CanonicalCookie::DebugString() const {
   return base::StringPrintf(
       "name: %s value: %s domain: %s path: %s creation: %"
       PRId64,
       name_.c_str(), value_.c_str(),
       domain_.c_str(), path_.c_str(),
       static_cast<int64>(creation_date_.ToTimeT()));
 }
 
 }  // namespace net