Implementation for chrome.certificateProvider.requestPin/stopPinRequest

chrome/browser/chromeos/certificate_provider/certificate_provider_service_factory.cc

 // Copyright 2015 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.
 
 #include "chrome/browser/chromeos/certificate_provider/certificate_provider_service_factory.h"
 
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/singleton.h"
+#include "base/rand_util.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/certificate_provider/certificate_provider_service.h"
 #include "chrome/browser/profiles/incognito_helpers.h"
 #include "chrome/common/extensions/api/certificate_provider.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "extensions/browser/event_listener_map.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/event_router_factory.h"
 #include "extensions/browser/extension_event_histogram_value.h"
 #include "extensions/browser/extension_registry.h"
@@ skipping 78 matching lines @@
     const std::string& extension_id,
     int request_id,
     net::SSLPrivateKey::Hash hash,
     const scoped_refptr<net::X509Certificate>& certificate,
     const std::string& digest) {
   const std::string event_name(api_cp::OnSignDigestRequested::kEventName);
   if (!event_router_->ExtensionHasEventListener(extension_id, event_name))
     return false;
 
   api_cp::SignRequest request;
+  uint64_t sign_request_id = base::RandUint64();
+  // If we hit the improbable case when generated ID exists already, we
+  // generate another ID.
+  while (!service_->AddSignRequestId(sign_request_id)) {
+    sign_request_id = base::RandUint64();
+  }

[stevenjb, 2016/08/09 21:04:39]

Why use random numbers here instead of an increasing static int which would have
no chance of repeating?

[igorcov1, 2016/08/10 18:05:03]

Security reasons. If an extension would know what's the next ID that will be
given it could spam requests with that ID.

+  request.sign_request_id = sign_request_id;
   switch (hash) {
     case net::SSLPrivateKey::Hash::MD5_SHA1:
       request.hash = api_cp::HASH_MD5_SHA1;
       break;
     case net::SSLPrivateKey::Hash::SHA1:
       request.hash = api_cp::HASH_SHA1;
       break;
     case net::SSLPrivateKey::Hash::SHA256:
       request.hash = api_cp::HASH_SHA256;
       break;
@@ skipping 70 matching lines @@
     content::BrowserContext* context) const {
   CertificateProviderService* const service = new CertificateProviderService();
   service->SetDelegate(base::WrapUnique(new DefaultDelegate(
       service,
       extensions::ExtensionRegistryFactory::GetForBrowserContext(context),
       extensions::EventRouterFactory::GetForBrowserContext(context))));
   return service;
 }
 
 }  // namespace chromeos