chrome/browser/net/ssl_config_service_manager_pref.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4 #include "chrome/browser/net/ssl_config_service_manager.h"
   5
   6 #include <algorithm>
   7 #include <string>
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "base/bind.h"
  12 #include "base/metrics/field_trial.h"
  13 #include "base/prefs/pref_change_registrar.h"
  14 #include "base/prefs/pref_member.h"
  15 #include "base/prefs/pref_registry_simple.h"
  16 #include "base/prefs/pref_service.h"
  17 #include "chrome/browser/chrome_notification_types.h"
  18 #include "chrome/common/chrome_switches.h"
  19 #include "chrome/common/pref_names.h"
  20 #include "components/content_settings/core/browser/content_settings_utils.h"
  21 #include "components/content_settings/core/common/content_settings.h"
  22 #include "components/google/core/browser/google_util.h"
  23 #include "content/public/browser/browser_thread.h"
  24 #include "net/socket/ssl_client_socket.h"
  25 #include "net/ssl/ssl_cipher_suite_names.h"
  26 #include "net/ssl/ssl_config_service.h"
  27 #include "url/gurl.h"
  28
  29 using content::BrowserThread;
  30
  31 namespace {
  32
  33 // Field trial for ClientHello padding.
  34 const char kClientHelloFieldTrialName[] = "FastRadioPadding";
  35 const char kClientHelloFieldTrialEnabledGroupName[] = "Enabled";
  36
  37 // Converts a ListValue of StringValues into a vector of strings. Any Values
  38 // which cannot be converted will be skipped.
  39 std::vector<std::string> ListValueToStringVector(const base::ListValue* value) {
  40   std::vector<std::string> results;
  41   results.reserve(value->GetSize());
  42   std::string s;
  43   for (base::ListValue::const_iterator it = value->begin(); it != value->end();
  44        ++it) {
  45     if (!(*it)->GetAsString(&s))
  46       continue;
  47     results.push_back(s);
  48   }
  49   return results;
  50 }
  51
  52 // Parses a vector of cipher suite strings, returning a sorted vector
  53 // containing the underlying SSL/TLS cipher suites. Unrecognized/invalid
  54 // cipher suites will be ignored.
  55 std::vector<uint16> ParseCipherSuites(
  56     const std::vector<std::string>& cipher_strings) {
  57   std::vector<uint16> cipher_suites;
  58   cipher_suites.reserve(cipher_strings.size());
  59
  60   for (std::vector<std::string>::const_iterator it = cipher_strings.begin();
  61        it != cipher_strings.end(); ++it) {
  62     uint16 cipher_suite = 0;
  63     if (!net::ParseSSLCipherString(*it, &cipher_suite)) {
  64       LOG(ERROR) << "Ignoring unrecognized or unparsable cipher suite: "
  65                  << *it;
  66       continue;
  67     }
  68     cipher_suites.push_back(cipher_suite);
  69   }
  70   std::sort(cipher_suites.begin(), cipher_suites.end());
  71   return cipher_suites;
  72 }
  73
  74 // Returns the SSL protocol version (as a uint16) represented by a string.
  75 // Returns 0 if the string is invalid.
  76 uint16 SSLProtocolVersionFromString(const std::string& version_str) {
  77   uint16 version = 0;  // Invalid.
  78   if (version_str == switches::kSSLVersionTLSv1) {
  79     version = net::SSL_PROTOCOL_VERSION_TLS1;
  80   } else if (version_str == switches::kSSLVersionTLSv11) {
  81     version = net::SSL_PROTOCOL_VERSION_TLS1_1;
  82   } else if (version_str == switches::kSSLVersionTLSv12) {
  83     version = net::SSL_PROTOCOL_VERSION_TLS1_2;
  84   }
  85   return version;
  86 }
  87
  88 }  // namespace
  89
  90 ////////////////////////////////////////////////////////////////////////////////
  91 //  SSLConfigServicePref
  92
  93 // An SSLConfigService which stores a cached version of the current SSLConfig
  94 // prefs, which are updated by SSLConfigServiceManagerPref when the prefs
  95 // change.
  96 class SSLConfigServicePref : public net::SSLConfigService {
  97  public:
  98   SSLConfigServicePref() {}
  99
 100   // Store SSL config settings in |config|. Must only be called from IO thread.
 101   void GetSSLConfig(net::SSLConfig* config) override;
 102
 103   bool SupportsFastradioPadding(const GURL& url) override;
 104
 105  private:
 106   // Allow the pref watcher to update our internal state.
 107   friend class SSLConfigServiceManagerPref;
 108
 109   ~SSLConfigServicePref() override {}
 110
 111   // This method is posted to the IO thread from the browser thread to carry the
 112   // new config information.
 113   void SetNewSSLConfig(const net::SSLConfig& new_config);
 114
 115   // Cached value of prefs, should only be accessed from IO thread.
 116   net::SSLConfig cached_config_;
 117
 118   DISALLOW_COPY_AND_ASSIGN(SSLConfigServicePref);
 119 };
 120
 121 void SSLConfigServicePref::GetSSLConfig(net::SSLConfig* config) {
 122   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 123   *config = cached_config_;
 124 }
 125
 126 bool SSLConfigServicePref::SupportsFastradioPadding(const GURL& url) {
 127   return google_util::IsGoogleHostname(url.host(),
 128                                        google_util::ALLOW_SUBDOMAIN);
 129 }
 130
 131 void SSLConfigServicePref::SetNewSSLConfig(
 132     const net::SSLConfig& new_config) {
 133   net::SSLConfig orig_config = cached_config_;
 134   cached_config_ = new_config;
 135   ProcessConfigUpdate(orig_config, new_config);
 136 }
 137
 138 ////////////////////////////////////////////////////////////////////////////////
 139 //  SSLConfigServiceManagerPref
 140
 141 // The manager for holding and updating an SSLConfigServicePref instance.
 142 class SSLConfigServiceManagerPref
 143     : public SSLConfigServiceManager {
 144  public:
 145   explicit SSLConfigServiceManagerPref(PrefService* local_state);
 146   ~SSLConfigServiceManagerPref() override {}
 147
 148   // Register local_state SSL preferences.
 149   static void RegisterPrefs(PrefRegistrySimple* registry);
 150
 151   net::SSLConfigService* Get() override;
 152
 153  private:
 154   // Callback for preference changes.  This will post the changes to the IO
 155   // thread with SetNewSSLConfig.
 156   void OnPreferenceChanged(PrefService* prefs,
 157                            const std::string& pref_name);
 158
 159   // Store SSL config settings in |config|, directly from the preferences. Must
 160   // only be called from UI thread.
 161   void GetSSLConfigFromPrefs(net::SSLConfig* config);
 162
 163   // Processes changes to the disabled cipher suites preference, updating the
 164   // cached list of parsed SSL/TLS cipher suites that are disabled.
 165   void OnDisabledCipherSuitesChange(PrefService* local_state);
 166
 167   PrefChangeRegistrar local_state_change_registrar_;
 168
 169   // The local_state prefs (should only be accessed from UI thread)
 170   BooleanPrefMember rev_checking_enabled_;
 171   BooleanPrefMember rev_checking_required_local_anchors_;
 172   StringPrefMember ssl_version_min_;
 173   StringPrefMember ssl_version_max_;
 174   StringPrefMember ssl_version_fallback_min_;
 175   BooleanPrefMember ssl_record_splitting_disabled_;
 176
 177   // The cached list of disabled SSL cipher suites.
 178   std::vector<uint16> disabled_cipher_suites_;
 179
 180   scoped_refptr<SSLConfigServicePref> ssl_config_service_;
 181
 182   DISALLOW_COPY_AND_ASSIGN(SSLConfigServiceManagerPref);
 183 };
 184
 185 SSLConfigServiceManagerPref::SSLConfigServiceManagerPref(
 186     PrefService* local_state)
 187     : ssl_config_service_(new SSLConfigServicePref()) {
 188   DCHECK(local_state);
 189
 190   PrefChangeRegistrar::NamedChangeCallback local_state_callback = base::Bind(
 191       &SSLConfigServiceManagerPref::OnPreferenceChanged,
 192       base::Unretained(this),
 193       local_state);
 194
 195   rev_checking_enabled_.Init(
 196       prefs::kCertRevocationCheckingEnabled, local_state, local_state_callback);
 197   rev_checking_required_local_anchors_.Init(
 198       prefs::kCertRevocationCheckingRequiredLocalAnchors,
 199       local_state,
 200       local_state_callback);
 201   ssl_version_min_.Init(
 202       prefs::kSSLVersionMin, local_state, local_state_callback);
 203   ssl_version_max_.Init(
 204       prefs::kSSLVersionMax, local_state, local_state_callback);
 205   ssl_version_fallback_min_.Init(
 206       prefs::kSSLVersionFallbackMin, local_state, local_state_callback);
 207   ssl_record_splitting_disabled_.Init(
 208       prefs::kDisableSSLRecordSplitting, local_state, local_state_callback);
 209
 210   local_state_change_registrar_.Init(local_state);
 211   local_state_change_registrar_.Add(
 212       prefs::kCipherSuiteBlacklist, local_state_callback);
 213
 214   OnDisabledCipherSuitesChange(local_state);
 215
 216   // Initialize from UI thread.  This is okay as there shouldn't be anything on
 217   // the IO thread trying to access it yet.
 218   GetSSLConfigFromPrefs(&ssl_config_service_->cached_config_);
 219 }
 220
 221 // static
 222 void SSLConfigServiceManagerPref::RegisterPrefs(PrefRegistrySimple* registry) {
 223   net::SSLConfig default_config;
 224   registry->RegisterBooleanPref(prefs::kCertRevocationCheckingEnabled,
 225                                 default_config.rev_checking_enabled);
 226   registry->RegisterBooleanPref(
 227       prefs::kCertRevocationCheckingRequiredLocalAnchors,
 228       default_config.rev_checking_required_local_anchors);
 229   registry->RegisterStringPref(prefs::kSSLVersionMin, std::string());
 230   registry->RegisterStringPref(prefs::kSSLVersionMax, std::string());
 231   registry->RegisterStringPref(prefs::kSSLVersionFallbackMin, std::string());
 232   registry->RegisterBooleanPref(prefs::kDisableSSLRecordSplitting,
 233                                 !default_config.false_start_enabled);
 234   registry->RegisterListPref(prefs::kCipherSuiteBlacklist);
 235 }
 236
 237 net::SSLConfigService* SSLConfigServiceManagerPref::Get() {
 238   return ssl_config_service_.get();
 239 }
 240
 241 void SSLConfigServiceManagerPref::OnPreferenceChanged(
 242     PrefService* prefs,
 243     const std::string& pref_name_in) {
 244   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 245   DCHECK(prefs);
 246   if (pref_name_in == prefs::kCipherSuiteBlacklist)
 247     OnDisabledCipherSuitesChange(prefs);
 248
 249   net::SSLConfig new_config;
 250   GetSSLConfigFromPrefs(&new_config);
 251
 252   // Post a task to |io_loop| with the new configuration, so it can
 253   // update |cached_config_|.
 254   BrowserThread::PostTask(
 255       BrowserThread::IO,
 256       FROM_HERE,
 257       base::Bind(
 258           &SSLConfigServicePref::SetNewSSLConfig,
 259           ssl_config_service_.get(),
 260           new_config));
 261 }
 262
 263 void SSLConfigServiceManagerPref::GetSSLConfigFromPrefs(
 264     net::SSLConfig* config) {
 265   // rev_checking_enabled was formerly a user-settable preference, but now
 266   // it is managed-only.
 267   if (rev_checking_enabled_.IsManaged())
 268     config->rev_checking_enabled = rev_checking_enabled_.GetValue();
 269   else
 270     config->rev_checking_enabled = false;
 271   config->rev_checking_required_local_anchors =
 272       rev_checking_required_local_anchors_.GetValue();
 273   std::string version_min_str = ssl_version_min_.GetValue();
 274   std::string version_max_str = ssl_version_max_.GetValue();
 275   std::string version_fallback_min_str = ssl_version_fallback_min_.GetValue();
 276   config->version_min = net::kDefaultSSLVersionMin;
 277   config->version_max = net::SSLClientSocket::GetMaxSupportedSSLVersion();
 278   config->version_fallback_min = net::kDefaultSSLVersionFallbackMin;
 279   uint16 version_min = SSLProtocolVersionFromString(version_min_str);
 280   uint16 version_max = SSLProtocolVersionFromString(version_max_str);
 281   uint16 version_fallback_min =
 282       SSLProtocolVersionFromString(version_fallback_min_str);
 283   if (version_min) {
 284     config->version_min = version_min;
 285   }
 286   if (version_max) {
 287     uint16 supported_version_max = config->version_max;
 288     config->version_max = std::min(supported_version_max, version_max);
 289   }
 290   if (version_fallback_min) {
 291     config->version_fallback_min = version_fallback_min;
 292   }
 293   config->disabled_cipher_suites = disabled_cipher_suites_;
 294   // disabling False Start also happens to disable record splitting.
 295   config->false_start_enabled = !ssl_record_splitting_disabled_.GetValue();
 296
 297   base::StringPiece group =
 298       base::FieldTrialList::FindFullName(kClientHelloFieldTrialName);
 299   if (group.starts_with(kClientHelloFieldTrialEnabledGroupName)) {
 300     config->fastradio_padding_enabled = true;
 301   }
 302 }
 303
 304 void SSLConfigServiceManagerPref::OnDisabledCipherSuitesChange(
 305     PrefService* local_state) {
 306   const base::ListValue* value =
 307       local_state->GetList(prefs::kCipherSuiteBlacklist);
 308   disabled_cipher_suites_ = ParseCipherSuites(ListValueToStringVector(value));
 309 }
 310
 311 ////////////////////////////////////////////////////////////////////////////////
 312 //  SSLConfigServiceManager
 313
 314 // static
 315 SSLConfigServiceManager* SSLConfigServiceManager::CreateDefaultManager(
 316     PrefService* local_state) {
 317   return new SSLConfigServiceManagerPref(local_state);
 318 }
 319
 320 // static
 321 void SSLConfigServiceManager::RegisterPrefs(PrefRegistrySimple* registry) {
 322   SSLConfigServiceManagerPref::RegisterPrefs(registry);
 323 }