Certificate Transparency: EV certificates whitelist support for ChromeOS

chrome/browser/component_updater/ev_whitelist_component_installer.cc

 // Copyright 2014 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/component_updater/ev_whitelist_component_installer.h"
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
+#include "base/numerics/safe_conversions.h"
 #include "base/path_service.h"
 #include "chrome/browser/net/packed_ct_ev_whitelist.h"
 #include "components/component_updater/component_updater_paths.h"
 #include "content/public/browser/browser_thread.h"
 #include "net/ssl/ssl_config_service.h"
 
 using component_updater::ComponentUpdateService;
 
 namespace {
 const base::FilePath::CharType kCompressedEVWhitelistFileName[] =
     FILE_PATH_LITERAL("ev_hashes_whitelist.bin");
+
+base::FilePath GetEVWhitelistFilePath(const base::FilePath& base_path) {
+  return base_path.Append(kCompressedEVWhitelistFileName);
+}
+
+void UpdateNewWhitelistData(const base::FilePath& new_whitelist_file,
+                            const base::FilePath& stored_whitelist_path) {
+  VLOG(1) << "Reading new EV whitelist from file: "
+          << new_whitelist_file.value();
+  std::string compressed_list;
+  if (!base::ReadFileToString(new_whitelist_file, &compressed_list)) {
+    VLOG(1) << "Failed reading from " << new_whitelist_file.value();
+    return;
+  }
+
+  scoped_refptr<net::ct::EVCertsWhitelist> new_whitelist(
+      new PackedEVCertsWhitelist(compressed_list));
+  if (!new_whitelist->IsValid()) {
+    VLOG(1) << "Failed uncompressing EV certs whitelist.";
+    return;
+  }
+
+  int list_size = base::checked_cast<int>(compressed_list.size());

[Sorin Jianu, 2014/11/07 17:30:44]

const?

Also, is the cast to int needed? What happens if we overflow?

[Eran Messeri, 2014/11/10 22:54:56]

Done
checked_cast has a DCHECK for these cases, doesn't it?
The list really shouldn't be >4GB in size, so I think a checked_cast here is
appropriate.

+  if (base::WriteFile(stored_whitelist_path, compressed_list.data(),
+                      list_size) != list_size) {
+    LOG(WARNING) << "Failed to save new EV whitelist to file.";
+  }
+
+  SetNewEVCertsWhitelist(new_whitelist);
+}
+
+void DoInitialLoadFromDisk(const base::FilePath& stored_whitelist_path) {
+  if (stored_whitelist_path.empty()) {
+    return;
+  }
+
+  VLOG(1) << "Initial load: reading EV whitelist from file: "
+          << stored_whitelist_path.value();
+  std::string compressed_list;
+  if (!base::ReadFileToString(stored_whitelist_path, &compressed_list)) {
+    VLOG(1) << "Failed reading from " << stored_whitelist_path.value();
+    return;
+  }
+
+  scoped_refptr<net::ct::EVCertsWhitelist> new_whitelist(
+      new PackedEVCertsWhitelist(compressed_list));
+  if (!new_whitelist->IsValid()) {
+    VLOG(1) << "Failed uncompressing EV certs whitelist.";
+    return;
+  }
+
+  VLOG(1) << "EV whitelist: Sucessfully loaded initial data.";
+  SetNewEVCertsWhitelist(new_whitelist);
+}
+
 }  // namespace
 
 namespace component_updater {
 
 // The SHA256 of the SubjectPublicKeyInfo used to sign the extension.
 // The extension id is: oafdbfcohdcjandcenmccfopbeklnicp
 const uint8_t kPublicKeySHA256[32] = {
     0xe0, 0x53, 0x15, 0x2e, 0x73, 0x29, 0x0d, 0x32, 0x4d, 0xc2, 0x25,
     0xef, 0x14, 0xab, 0xd8, 0x2f, 0x84, 0xf5, 0x85, 0x9e, 0xc0, 0xfa,
     0x94, 0xbc, 0x99, 0xc9, 0x5a, 0x27, 0x55, 0x19, 0x83, 0xef};
 
 const char kEVWhitelistManifestName[] = "EV Certs CT whitelist";
 
-EVWhitelistComponentInstallerTraits::EVWhitelistComponentInstallerTraits() {
+EVWhitelistComponentInstallerTraits::EVWhitelistComponentInstallerTraits(
+    const base::FilePath& base_path)
+    : ev_whitelist_path_(GetEVWhitelistFilePath(base_path)) {
 }
 
 bool EVWhitelistComponentInstallerTraits::CanAutoUpdate() const {
   return true;
 }
 
 bool EVWhitelistComponentInstallerTraits::OnCustomInstall(
     const base::DictionaryValue& manifest,
     const base::FilePath& install_dir) {
   VLOG(1) << "Entering EVWhitelistComponentInstallerTraits::OnCustomInstall.";
@@ skipping 11 matching lines @@
 
 void EVWhitelistComponentInstallerTraits::ComponentReady(
     const base::Version& version,
     const base::FilePath& path,
     scoped_ptr<base::DictionaryValue> manifest) {
   VLOG(1) << "Component ready, version " << version.GetString() << " in "
           << path.value();
 
   const base::FilePath whitelist_file = GetInstalledPath(path);
   content::BrowserThread::PostBlockingPoolTask(
-      FROM_HERE, base::Bind(&SetEVWhitelistFromFile, whitelist_file));
+      FROM_HERE,
+      base::Bind(&UpdateNewWhitelistData, whitelist_file, ev_whitelist_path_));
 }
 
 bool EVWhitelistComponentInstallerTraits::VerifyInstallation(
     const base::DictionaryValue& manifest,
     const base::FilePath& install_dir) const {
   const base::FilePath expected_file = GetInstalledPath(install_dir);
   VLOG(1) << "Verifying install: " << expected_file.value();
   if (!base::PathExists(expected_file)) {
     VLOG(1) << "File missing.";
     return false;
@@ skipping 19 matching lines @@
 void EVWhitelistComponentInstallerTraits::GetHash(
     std::vector<uint8_t>* hash) const {
   hash->assign(kPublicKeySHA256,
                kPublicKeySHA256 + arraysize(kPublicKeySHA256));
 }
 
 std::string EVWhitelistComponentInstallerTraits::GetName() const {
   return kEVWhitelistManifestName;
 }
 
-void RegisterEVWhitelistComponent(ComponentUpdateService* cus) {
+void RegisterEVWhitelistComponent(ComponentUpdateService* cus,
+                                  const base::FilePath& path) {
   VLOG(1) << "Registering EV whitelist component.";
 
   scoped_ptr<ComponentInstallerTraits> traits(
-      new EVWhitelistComponentInstallerTraits());
+      new EVWhitelistComponentInstallerTraits(path));
   // |cus| will take ownership of |installer| during installer->Register(cus).
   DefaultComponentInstaller* installer =
       new DefaultComponentInstaller(traits.Pass());
   installer->Register(cus);
+
+  if (!content::BrowserThread::PostTask(
+          content::BrowserThread::FILE, FROM_HERE,

[Sorin Jianu, 2014/11/07 17:30:44]

Can we use a thread from the blocking pool for this instead of the FILE thread?
As a general idea, we want to be off the FILE thread as much as possible.

[Eran Messeri, 2014/11/10 22:54:56]

Done.

+          base::Bind(&DoInitialLoadFromDisk, GetEVWhitelistFilePath(path)))) {
+    NOTREACHED();
+  }
 }
 
 }  // namespace component_updater