net/quic/crypto/quic_crypto_client_config.cc

   1 // Copyright 2013 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
   5 #include "net/quic/crypto/quic_crypto_client_config.h"
   6
   7 #include "base/metrics/histogram.h"
   8 #include "base/metrics/sparse_histogram.h"
   9 #include "base/stl_util.h"
  10 #include "base/strings/string_util.h"
  11 #include "net/quic/crypto/cert_compressor.h"
  12 #include "net/quic/crypto/chacha20_poly1305_encrypter.h"
  13 #include "net/quic/crypto/channel_id.h"
  14 #include "net/quic/crypto/common_cert_set.h"
  15 #include "net/quic/crypto/crypto_framer.h"
  16 #include "net/quic/crypto/crypto_utils.h"
  17 #include "net/quic/crypto/curve25519_key_exchange.h"
  18 #include "net/quic/crypto/key_exchange.h"
  19 #include "net/quic/crypto/p256_key_exchange.h"
  20 #include "net/quic/crypto/proof_verifier.h"
  21 #include "net/quic/crypto/quic_encrypter.h"
  22 #include "net/quic/quic_utils.h"
  23
  24 using base::StringPiece;
  25 using std::map;
  26 using std::string;
  27 using std::vector;
  28
  29 namespace net {
  30
  31 namespace {
  32
  33 // Tracks the reason (the state of the server config) for sending inchoate
  34 // ClientHello to the server.
  35 void RecordInchoateClientHelloReason(
  36     QuicCryptoClientConfig::CachedState::ServerConfigState state) {
  37   UMA_HISTOGRAM_ENUMERATION(
  38       "Net.QuicInchoateClientHelloReason", state,
  39       QuicCryptoClientConfig::CachedState::SERVER_CONFIG_COUNT);
  40 }
  41
  42 // Tracks the state of the QUIC server information loaded from the disk cache.
  43 void RecordDiskCacheServerConfigState(
  44     QuicCryptoClientConfig::CachedState::ServerConfigState state) {
  45   UMA_HISTOGRAM_ENUMERATION(
  46       "Net.QuicServerInfo.DiskCacheState", state,
  47       QuicCryptoClientConfig::CachedState::SERVER_CONFIG_COUNT);
  48 }
  49
  50 }  // namespace
  51
  52 QuicCryptoClientConfig::QuicCryptoClientConfig()
  53     : disable_ecdsa_(false) {
  54   SetDefaults();
  55 }
  56
  57 QuicCryptoClientConfig::~QuicCryptoClientConfig() {
  58   STLDeleteValues(&cached_states_);
  59 }
  60
  61 QuicCryptoClientConfig::CachedState::CachedState()
  62     : server_config_valid_(false),
  63       generation_counter_(0) {}
  64
  65 QuicCryptoClientConfig::CachedState::~CachedState() {}
  66
  67 bool QuicCryptoClientConfig::CachedState::IsComplete(QuicWallTime now) const {
  68   if (server_config_.empty()) {
  69     RecordInchoateClientHelloReason(SERVER_CONFIG_EMPTY);
  70     return false;
  71   }
  72
  73   if (!server_config_valid_) {
  74     RecordInchoateClientHelloReason(SERVER_CONFIG_INVALID);
  75     return false;
  76   }
  77
  78   const CryptoHandshakeMessage* scfg = GetServerConfig();
  79   if (!scfg) {
  80     // Should be impossible short of cache corruption.
  81     DCHECK(false);
  82     RecordInchoateClientHelloReason(SERVER_CONFIG_CORRUPTED);
  83     return false;
  84   }
  85
  86   uint64 expiry_seconds;
  87   if (scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
  88     RecordInchoateClientHelloReason(SERVER_CONFIG_INVALID_EXPIRY);
  89     return false;
  90   }
  91   if (now.ToUNIXSeconds() >= expiry_seconds) {
  92     UMA_HISTOGRAM_CUSTOM_TIMES(
  93         "Net.QuicClientHelloServerConfig.InvalidDuration",
  94         base::TimeDelta::FromSeconds(now.ToUNIXSeconds() - expiry_seconds),
  95         base::TimeDelta::FromMinutes(1), base::TimeDelta::FromDays(20), 50);
  96     RecordInchoateClientHelloReason(SERVER_CONFIG_EXPIRED);
  97     return false;
  98   }
  99
 100   return true;
 101 }
 102
 103 bool QuicCryptoClientConfig::CachedState::IsEmpty() const {
 104   return server_config_.empty();
 105 }
 106
 107 const CryptoHandshakeMessage*
 108 QuicCryptoClientConfig::CachedState::GetServerConfig() const {
 109   if (server_config_.empty()) {
 110     return nullptr;
 111   }
 112
 113   if (!scfg_.get()) {
 114     scfg_.reset(CryptoFramer::ParseMessage(server_config_));
 115     DCHECK(scfg_.get());
 116   }
 117   return scfg_.get();
 118 }
 119
 120 QuicCryptoClientConfig::CachedState::ServerConfigState
 121 QuicCryptoClientConfig::CachedState::SetServerConfig(
 122     StringPiece server_config, QuicWallTime now, string* error_details) {
 123   const bool matches_existing = server_config == server_config_;
 124
 125   // Even if the new server config matches the existing one, we still wish to
 126   // reject it if it has expired.
 127   scoped_ptr<CryptoHandshakeMessage> new_scfg_storage;
 128   const CryptoHandshakeMessage* new_scfg;
 129
 130   if (!matches_existing) {
 131     new_scfg_storage.reset(CryptoFramer::ParseMessage(server_config));
 132     new_scfg = new_scfg_storage.get();
 133   } else {
 134     new_scfg = GetServerConfig();
 135   }
 136
 137   if (!new_scfg) {
 138     *error_details = "SCFG invalid";
 139     return SERVER_CONFIG_INVALID;
 140   }
 141
 142   uint64 expiry_seconds;
 143   if (new_scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
 144     *error_details = "SCFG missing EXPY";
 145     return SERVER_CONFIG_INVALID_EXPIRY;
 146   }
 147
 148   if (now.ToUNIXSeconds() >= expiry_seconds) {
 149     *error_details = "SCFG has expired";
 150     return SERVER_CONFIG_EXPIRED;
 151   }
 152
 153   if (!matches_existing) {
 154     server_config_ = server_config.as_string();
 155     SetProofInvalid();
 156     scfg_.reset(new_scfg_storage.release());
 157   }
 158   return SERVER_CONFIG_VALID;
 159 }
 160
 161 void QuicCryptoClientConfig::CachedState::InvalidateServerConfig() {
 162   server_config_.clear();
 163   scfg_.reset();
 164   SetProofInvalid();
 165 }
 166
 167 void QuicCryptoClientConfig::CachedState::SetProof(const vector<string>& certs,
 168                                                    StringPiece signature) {
 169   bool has_changed =
 170       signature != server_config_sig_ || certs_.size() != certs.size();
 171
 172   if (!has_changed) {
 173     for (size_t i = 0; i < certs_.size(); i++) {
 174       if (certs_[i] != certs[i]) {
 175         has_changed = true;
 176         break;
 177       }
 178     }
 179   }
 180
 181   if (!has_changed) {
 182     return;
 183   }
 184
 185   // If the proof has changed then it needs to be revalidated.
 186   SetProofInvalid();
 187   certs_ = certs;
 188   server_config_sig_ = signature.as_string();
 189 }
 190
 191 void QuicCryptoClientConfig::CachedState::Clear() {
 192   server_config_.clear();
 193   source_address_token_.clear();
 194   certs_.clear();
 195   server_config_sig_.clear();
 196   server_config_valid_ = false;
 197   proof_verify_details_.reset();
 198   scfg_.reset();
 199   ++generation_counter_;
 200 }
 201
 202 void QuicCryptoClientConfig::CachedState::ClearProof() {
 203   SetProofInvalid();
 204   certs_.clear();
 205   server_config_sig_.clear();
 206 }
 207
 208 void QuicCryptoClientConfig::CachedState::SetProofValid() {
 209   server_config_valid_ = true;
 210 }
 211
 212 void QuicCryptoClientConfig::CachedState::SetProofInvalid() {
 213   server_config_valid_ = false;
 214   ++generation_counter_;
 215 }
 216
 217 bool QuicCryptoClientConfig::CachedState::Initialize(
 218     StringPiece server_config,
 219     StringPiece source_address_token,
 220     const vector<string>& certs,
 221     StringPiece signature,
 222     QuicWallTime now) {
 223   DCHECK(server_config_.empty());
 224
 225   if (server_config.empty()) {
 226     RecordDiskCacheServerConfigState(SERVER_CONFIG_EMPTY);
 227     return false;
 228   }
 229
 230   string error_details;
 231   ServerConfigState state = SetServerConfig(server_config, now,
 232                                             &error_details);
 233   RecordDiskCacheServerConfigState(state);
 234   if (state != SERVER_CONFIG_VALID) {
 235     DVLOG(1) << "SetServerConfig failed with " << error_details;
 236     return false;
 237   }
 238
 239   signature.CopyToString(&server_config_sig_);
 240   source_address_token.CopyToString(&source_address_token_);
 241   certs_ = certs;
 242   return true;
 243 }
 244
 245 const string& QuicCryptoClientConfig::CachedState::server_config() const {
 246   return server_config_;
 247 }
 248
 249 const string&
 250 QuicCryptoClientConfig::CachedState::source_address_token() const {
 251   return source_address_token_;
 252 }
 253
 254 const vector<string>& QuicCryptoClientConfig::CachedState::certs() const {
 255   return certs_;
 256 }
 257
 258 const string& QuicCryptoClientConfig::CachedState::signature() const {
 259   return server_config_sig_;
 260 }
 261
 262 bool QuicCryptoClientConfig::CachedState::proof_valid() const {
 263   return server_config_valid_;
 264 }
 265
 266 uint64 QuicCryptoClientConfig::CachedState::generation_counter() const {
 267   return generation_counter_;
 268 }
 269
 270 const ProofVerifyDetails*
 271 QuicCryptoClientConfig::CachedState::proof_verify_details() const {
 272   return proof_verify_details_.get();
 273 }
 274
 275 void QuicCryptoClientConfig::CachedState::set_source_address_token(
 276     StringPiece token) {
 277   source_address_token_ = token.as_string();
 278 }
 279
 280 void QuicCryptoClientConfig::CachedState::SetProofVerifyDetails(
 281     ProofVerifyDetails* details) {
 282   proof_verify_details_.reset(details);
 283 }
 284
 285 void QuicCryptoClientConfig::CachedState::InitializeFrom(
 286     const QuicCryptoClientConfig::CachedState& other) {
 287   DCHECK(server_config_.empty());
 288   DCHECK(!server_config_valid_);
 289   server_config_ = other.server_config_;
 290   source_address_token_ = other.source_address_token_;
 291   certs_ = other.certs_;
 292   server_config_sig_ = other.server_config_sig_;
 293   server_config_valid_ = other.server_config_valid_;
 294   if (other.proof_verify_details_.get() != nullptr) {
 295     proof_verify_details_.reset(other.proof_verify_details_->Clone());
 296   }
 297   ++generation_counter_;
 298 }
 299
 300 void QuicCryptoClientConfig::SetDefaults() {
 301   // Key exchange methods.
 302   kexs.resize(2);
 303   kexs[0] = kC255;
 304   kexs[1] = kP256;
 305
 306   // Authenticated encryption algorithms. Prefer ChaCha20 by default.
 307   aead.clear();
 308   if (ChaCha20Poly1305Encrypter::IsSupported()) {
 309     aead.push_back(kCC12);
 310   }
 311   aead.push_back(kAESG);
 312
 313   disable_ecdsa_ = false;
 314 }
 315
 316 QuicCryptoClientConfig::CachedState* QuicCryptoClientConfig::LookupOrCreate(
 317     const QuicServerId& server_id) {
 318   CachedStateMap::const_iterator it = cached_states_.find(server_id);
 319   if (it != cached_states_.end()) {
 320     return it->second;
 321   }
 322
 323   CachedState* cached = new CachedState;
 324   cached_states_.insert(std::make_pair(server_id, cached));
 325   bool cache_populated = PopulateFromCanonicalConfig(server_id, cached);
 326   UMA_HISTOGRAM_BOOLEAN(
 327       "Net.QuicCryptoClientConfig.PopulatedFromCanonicalConfig",
 328       cache_populated);
 329   return cached;
 330 }
 331
 332 void QuicCryptoClientConfig::ClearCachedStates() {
 333   for (CachedStateMap::const_iterator it = cached_states_.begin();
 334        it != cached_states_.end(); ++it) {
 335     it->second->Clear();
 336   }
 337 }
 338
 339 void QuicCryptoClientConfig::FillInchoateClientHello(
 340     const QuicServerId& server_id,
 341     const QuicVersion preferred_version,
 342     const CachedState* cached,
 343     QuicCryptoNegotiatedParameters* out_params,
 344     CryptoHandshakeMessage* out) const {
 345   out->set_tag(kCHLO);
 346   out->set_minimum_size(kClientHelloMinimumSize);
 347
 348   // Server name indication. We only send SNI if it's a valid domain name, as
 349   // per the spec.
 350   if (CryptoUtils::IsValidSNI(server_id.host())) {
 351     out->SetStringPiece(kSNI, server_id.host());
 352   }
 353   out->SetValue(kVER, QuicVersionToQuicTag(preferred_version));
 354
 355   if (!user_agent_id_.empty()) {
 356     out->SetStringPiece(kUAID, user_agent_id_);
 357   }
 358
 359   if (!cached->source_address_token().empty()) {
 360     out->SetStringPiece(kSourceAddressTokenTag, cached->source_address_token());
 361   }
 362
 363   if (server_id.is_https()) {
 364     if (disable_ecdsa_) {
 365       out->SetTaglist(kPDMD, kX59R, 0);
 366     } else {
 367       out->SetTaglist(kPDMD, kX509, 0);
 368     }
 369   }
 370
 371   if (common_cert_sets) {
 372     out->SetStringPiece(kCCS, common_cert_sets->GetCommonHashes());
 373   }
 374
 375   const vector<string>& certs = cached->certs();
 376   // We save |certs| in the QuicCryptoNegotiatedParameters so that, if the
 377   // client config is being used for multiple connections, another connection
 378   // doesn't update the cached certificates and cause us to be unable to
 379   // process the server's compressed certificate chain.
 380   out_params->cached_certs = certs;
 381   if (!certs.empty()) {
 382     vector<uint64> hashes;
 383     hashes.reserve(certs.size());
 384     for (vector<string>::const_iterator i = certs.begin();
 385          i != certs.end(); ++i) {
 386       hashes.push_back(QuicUtils::FNV1a_64_Hash(i->data(), i->size()));
 387     }
 388     out->SetVector(kCCRT, hashes);
 389   }
 390 }
 391
 392 QuicErrorCode QuicCryptoClientConfig::FillClientHello(
 393     const QuicServerId& server_id,
 394     QuicConnectionId connection_id,
 395     const QuicVersion preferred_version,
 396     const CachedState* cached,
 397     QuicWallTime now,
 398     QuicRandom* rand,
 399     const ChannelIDKey* channel_id_key,
 400     QuicCryptoNegotiatedParameters* out_params,
 401     CryptoHandshakeMessage* out,
 402     string* error_details) const {
 403   DCHECK(error_details != nullptr);
 404
 405   FillInchoateClientHello(server_id, preferred_version, cached,
 406                           out_params, out);
 407
 408   const CryptoHandshakeMessage* scfg = cached->GetServerConfig();
 409   if (!scfg) {
 410     // This should never happen as our caller should have checked
 411     // cached->IsComplete() before calling this function.
 412     *error_details = "Handshake not ready";
 413     return QUIC_CRYPTO_INTERNAL_ERROR;
 414   }
 415
 416   StringPiece scid;
 417   if (!scfg->GetStringPiece(kSCID, &scid)) {
 418     *error_details = "SCFG missing SCID";
 419     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 420   }
 421   out->SetStringPiece(kSCID, scid);
 422
 423   const QuicTag* their_aeads;
 424   const QuicTag* their_key_exchanges;
 425   size_t num_their_aeads, num_their_key_exchanges;
 426   if (scfg->GetTaglist(kAEAD, &their_aeads,
 427                        &num_their_aeads) != QUIC_NO_ERROR ||
 428       scfg->GetTaglist(kKEXS, &their_key_exchanges,
 429                        &num_their_key_exchanges) != QUIC_NO_ERROR) {
 430     *error_details = "Missing AEAD or KEXS";
 431     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 432   }
 433
 434   // AEAD: the work loads on the client and server are symmetric. Since the
 435   // client is more likely to be CPU-constrained, break the tie by favoring
 436   // the client's preference.
 437   // Key exchange: the client does more work than the server, so favor the
 438   // client's preference.
 439   size_t key_exchange_index;
 440   if (!QuicUtils::FindMutualTag(
 441           aead, their_aeads, num_their_aeads, QuicUtils::LOCAL_PRIORITY,
 442           &out_params->aead, nullptr) ||
 443       !QuicUtils::FindMutualTag(
 444           kexs, their_key_exchanges, num_their_key_exchanges,
 445           QuicUtils::LOCAL_PRIORITY, &out_params->key_exchange,
 446           &key_exchange_index)) {
 447     *error_details = "Unsupported AEAD or KEXS";
 448     return QUIC_CRYPTO_NO_SUPPORT;
 449   }
 450   out->SetTaglist(kAEAD, out_params->aead, 0);
 451   out->SetTaglist(kKEXS, out_params->key_exchange, 0);
 452
 453   StringPiece public_value;
 454   if (scfg->GetNthValue24(kPUBS, key_exchange_index, &public_value) !=
 455           QUIC_NO_ERROR) {
 456     *error_details = "Missing public value";
 457     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 458   }
 459
 460   StringPiece orbit;
 461   if (!scfg->GetStringPiece(kORBT, &orbit) || orbit.size() != kOrbitSize) {
 462     *error_details = "SCFG missing OBIT";
 463     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 464   }
 465
 466   CryptoUtils::GenerateNonce(now, rand, orbit, &out_params->client_nonce);
 467   out->SetStringPiece(kNONC, out_params->client_nonce);
 468   if (!out_params->server_nonce.empty()) {
 469     out->SetStringPiece(kServerNonceTag, out_params->server_nonce);
 470   }
 471
 472   switch (out_params->key_exchange) {
 473     case kC255:
 474       out_params->client_key_exchange.reset(Curve25519KeyExchange::New(
 475           Curve25519KeyExchange::NewPrivateKey(rand)));
 476       break;
 477     case kP256:
 478       out_params->client_key_exchange.reset(P256KeyExchange::New(
 479           P256KeyExchange::NewPrivateKey()));
 480       break;
 481     default:
 482       DCHECK(false);
 483       *error_details = "Configured to support an unknown key exchange";
 484       return QUIC_CRYPTO_INTERNAL_ERROR;
 485   }
 486
 487   if (!out_params->client_key_exchange->CalculateSharedKey(
 488           public_value, &out_params->initial_premaster_secret)) {
 489     *error_details = "Key exchange failure";
 490     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 491   }
 492   out->SetStringPiece(kPUBS, out_params->client_key_exchange->public_value());
 493
 494   if (channel_id_key) {
 495     // In order to calculate the encryption key for the CETV block we need to
 496     // serialise the client hello as it currently is (i.e. without the CETV
 497     // block). For this, the client hello is serialized without padding.
 498     const size_t orig_min_size = out->minimum_size();
 499     out->set_minimum_size(0);
 500
 501     CryptoHandshakeMessage cetv;
 502     cetv.set_tag(kCETV);
 503
 504     string hkdf_input;
 505     const QuicData& client_hello_serialized = out->GetSerialized();
 506     hkdf_input.append(QuicCryptoConfig::kCETVLabel,
 507                       strlen(QuicCryptoConfig::kCETVLabel) + 1);
 508     hkdf_input.append(reinterpret_cast<char*>(&connection_id),
 509                       sizeof(connection_id));
 510     hkdf_input.append(client_hello_serialized.data(),
 511                       client_hello_serialized.length());
 512     hkdf_input.append(cached->server_config());
 513
 514     string key = channel_id_key->SerializeKey();
 515     string signature;
 516     if (!channel_id_key->Sign(hkdf_input, &signature)) {
 517       *error_details = "Channel ID signature failed";
 518       return QUIC_INVALID_CHANNEL_ID_SIGNATURE;
 519     }
 520
 521     cetv.SetStringPiece(kCIDK, key);
 522     cetv.SetStringPiece(kCIDS, signature);
 523
 524     CrypterPair crypters;
 525     if (!CryptoUtils::DeriveKeys(
 526             out_params->initial_premaster_secret, out_params->aead,
 527             out_params->client_nonce, out_params->server_nonce, hkdf_input,
 528             Perspective::IS_CLIENT, &crypters, nullptr /* subkey secret */)) {
 529       *error_details = "Symmetric key setup failed";
 530       return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 531     }
 532
 533     const QuicData& cetv_plaintext = cetv.GetSerialized();
 534     const size_t encrypted_len =
 535         crypters.encrypter->GetCiphertextSize(cetv_plaintext.length());
 536     scoped_ptr<char[]> output(new char[encrypted_len]);
 537     size_t output_size = 0;
 538     if (!crypters.encrypter->EncryptPacket(
 539             0 /* sequence number */, StringPiece() /* associated data */,
 540             cetv_plaintext.AsStringPiece(), output.get(), &output_size,
 541             encrypted_len)) {
 542       *error_details = "Packet encryption failed";
 543       return QUIC_ENCRYPTION_FAILURE;
 544     }
 545
 546     out->SetStringPiece(kCETV, StringPiece(output.get(), output_size));
 547     out->MarkDirty();
 548
 549     out->set_minimum_size(orig_min_size);
 550   }
 551
 552   // Derive the symmetric keys and set up the encrypters and decrypters.
 553   // Set the following members of out_params:
 554   //   out_params->hkdf_input_suffix
 555   //   out_params->initial_crypters
 556   out_params->hkdf_input_suffix.clear();
 557   out_params->hkdf_input_suffix.append(reinterpret_cast<char*>(&connection_id),
 558                                        sizeof(connection_id));
 559   const QuicData& client_hello_serialized = out->GetSerialized();
 560   out_params->hkdf_input_suffix.append(client_hello_serialized.data(),
 561                                        client_hello_serialized.length());
 562   out_params->hkdf_input_suffix.append(cached->server_config());
 563
 564   string hkdf_input;
 565   const size_t label_len = strlen(QuicCryptoConfig::kInitialLabel) + 1;
 566   hkdf_input.reserve(label_len + out_params->hkdf_input_suffix.size());
 567   hkdf_input.append(QuicCryptoConfig::kInitialLabel, label_len);
 568   hkdf_input.append(out_params->hkdf_input_suffix);
 569
 570   if (!CryptoUtils::DeriveKeys(
 571           out_params->initial_premaster_secret, out_params->aead,
 572           out_params->client_nonce, out_params->server_nonce, hkdf_input,
 573           Perspective::IS_CLIENT, &out_params->initial_crypters,
 574           nullptr /* subkey secret */)) {
 575     *error_details = "Symmetric key setup failed";
 576     return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 577   }
 578
 579   return QUIC_NO_ERROR;
 580 }
 581
 582 QuicErrorCode QuicCryptoClientConfig::CacheNewServerConfig(
 583     const CryptoHandshakeMessage& message,
 584     QuicWallTime now,
 585     const vector<string>& cached_certs,
 586     CachedState* cached,
 587     string* error_details) {
 588   DCHECK(error_details != nullptr);
 589
 590   StringPiece scfg;
 591   if (!message.GetStringPiece(kSCFG, &scfg)) {
 592     *error_details = "Missing SCFG";
 593     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 594   }
 595
 596   CachedState::ServerConfigState state = cached->SetServerConfig(
 597       scfg, now, error_details);
 598   if (state == CachedState::SERVER_CONFIG_EXPIRED) {
 599     return QUIC_CRYPTO_SERVER_CONFIG_EXPIRED;
 600   }
 601   // TODO(rtenneti): Return more specific error code than returning
 602   // QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER.
 603   if (state != CachedState::SERVER_CONFIG_VALID) {
 604     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 605   }
 606
 607   StringPiece token;
 608   if (message.GetStringPiece(kSourceAddressTokenTag, &token)) {
 609     cached->set_source_address_token(token);
 610   }
 611
 612   StringPiece proof, cert_bytes;
 613   bool has_proof = message.GetStringPiece(kPROF, &proof);
 614   bool has_cert = message.GetStringPiece(kCertificateTag, &cert_bytes);
 615   if (has_proof && has_cert) {
 616     vector<string> certs;
 617     if (!CertCompressor::DecompressChain(cert_bytes, cached_certs,
 618                                          common_cert_sets, &certs)) {
 619       *error_details = "Certificate data invalid";
 620       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 621     }
 622
 623     cached->SetProof(certs, proof);
 624   } else {
 625     if (proof_verifier() != nullptr) {
 626       // Secure QUIC: clear existing proof as we have been sent a new SCFG
 627       // without matching proof/certs.
 628       cached->ClearProof();
 629     }
 630
 631     if (has_proof && !has_cert) {
 632       *error_details = "Certificate missing";
 633       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 634     }
 635
 636     if (!has_proof && has_cert) {
 637       *error_details = "Proof missing";
 638       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 639     }
 640   }
 641
 642   return QUIC_NO_ERROR;
 643 }
 644
 645 QuicErrorCode QuicCryptoClientConfig::ProcessRejection(
 646     const CryptoHandshakeMessage& rej,
 647     QuicWallTime now,
 648     CachedState* cached,
 649     bool is_https,
 650     QuicCryptoNegotiatedParameters* out_params,
 651     string* error_details) {
 652   DCHECK(error_details != nullptr);
 653
 654   if (rej.tag() != kREJ) {
 655     *error_details = "Message is not REJ";
 656     return QUIC_CRYPTO_INTERNAL_ERROR;
 657   }
 658
 659   QuicErrorCode error = CacheNewServerConfig(rej, now, out_params->cached_certs,
 660                                              cached, error_details);
 661   if (error != QUIC_NO_ERROR) {
 662     return error;
 663   }
 664
 665   StringPiece nonce;
 666   if (rej.GetStringPiece(kServerNonceTag, &nonce)) {
 667     out_params->server_nonce = nonce.as_string();
 668   }
 669
 670   const uint32* reject_reasons;
 671   size_t num_reject_reasons;
 672   static_assert(sizeof(QuicTag) == sizeof(uint32), "header out of sync");
 673   if (rej.GetTaglist(kRREJ, &reject_reasons,
 674                      &num_reject_reasons) == QUIC_NO_ERROR) {
 675     uint32 packed_error = 0;
 676     for (size_t i = 0; i < num_reject_reasons; ++i) {
 677       // HANDSHAKE_OK is 0 and don't report that as error.
 678       if (reject_reasons[i] == HANDSHAKE_OK || reject_reasons[i] >= 32) {
 679         continue;
 680       }
 681       HandshakeFailureReason reason =
 682           static_cast<HandshakeFailureReason>(reject_reasons[i]);
 683       packed_error |= 1 << (reason - 1);
 684     }
 685     DVLOG(1) << "Reasons for rejection: " << packed_error;
 686     if (is_https) {
 687       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons.Secure",
 688                                   packed_error);
 689     } else {
 690       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons.Insecure",
 691                                   packed_error);
 692     }
 693   }
 694
 695   return QUIC_NO_ERROR;
 696 }
 697
 698 QuicErrorCode QuicCryptoClientConfig::ProcessServerHello(
 699     const CryptoHandshakeMessage& server_hello,
 700     QuicConnectionId connection_id,
 701     const QuicVersionVector& negotiated_versions,
 702     CachedState* cached,
 703     QuicCryptoNegotiatedParameters* out_params,
 704     string* error_details) {
 705   DCHECK(error_details != nullptr);
 706
 707   if (server_hello.tag() != kSHLO) {
 708     *error_details = "Bad tag";
 709     return QUIC_INVALID_CRYPTO_MESSAGE_TYPE;
 710   }
 711
 712   const QuicTag* supported_version_tags;
 713   size_t num_supported_versions;
 714
 715   if (server_hello.GetTaglist(kVER, &supported_version_tags,
 716                               &num_supported_versions) != QUIC_NO_ERROR) {
 717     *error_details = "server hello missing version list";
 718     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 719   }
 720   if (!negotiated_versions.empty()) {
 721     bool mismatch = num_supported_versions != negotiated_versions.size();
 722     for (size_t i = 0; i < num_supported_versions && !mismatch; ++i) {
 723       mismatch = QuicTagToQuicVersion(supported_version_tags[i]) !=
 724           negotiated_versions[i];
 725     }
 726     // The server sent a list of supported versions, and the connection
 727     // reports that there was a version negotiation during the handshake.
 728       // Ensure that these two lists are identical.
 729     if (mismatch) {
 730       *error_details = "Downgrade attack detected";
 731       return QUIC_VERSION_NEGOTIATION_MISMATCH;
 732     }
 733   }
 734
 735   // Learn about updated source address tokens.
 736   StringPiece token;
 737   if (server_hello.GetStringPiece(kSourceAddressTokenTag, &token)) {
 738     cached->set_source_address_token(token);
 739   }
 740
 741   // TODO(agl):
 742   //   learn about updated SCFGs.
 743
 744   StringPiece public_value;
 745   if (!server_hello.GetStringPiece(kPUBS, &public_value)) {
 746     *error_details = "server hello missing forward secure public value";
 747     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 748   }
 749
 750   if (!out_params->client_key_exchange->CalculateSharedKey(
 751           public_value, &out_params->forward_secure_premaster_secret)) {
 752     *error_details = "Key exchange failure";
 753     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 754   }
 755
 756   string hkdf_input;
 757   const size_t label_len = strlen(QuicCryptoConfig::kForwardSecureLabel) + 1;
 758   hkdf_input.reserve(label_len + out_params->hkdf_input_suffix.size());
 759   hkdf_input.append(QuicCryptoConfig::kForwardSecureLabel, label_len);
 760   hkdf_input.append(out_params->hkdf_input_suffix);
 761
 762   if (!CryptoUtils::DeriveKeys(
 763           out_params->forward_secure_premaster_secret, out_params->aead,
 764           out_params->client_nonce, out_params->server_nonce, hkdf_input,
 765           Perspective::IS_CLIENT, &out_params->forward_secure_crypters,
 766           &out_params->subkey_secret)) {
 767     *error_details = "Symmetric key setup failed";
 768     return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 769   }
 770
 771   return QUIC_NO_ERROR;
 772 }
 773
 774 QuicErrorCode QuicCryptoClientConfig::ProcessServerConfigUpdate(
 775     const CryptoHandshakeMessage& server_config_update,
 776     QuicWallTime now,
 777     CachedState* cached,
 778     QuicCryptoNegotiatedParameters* out_params,
 779     string* error_details) {
 780   DCHECK(error_details != nullptr);
 781
 782   if (server_config_update.tag() != kSCUP) {
 783     *error_details = "ServerConfigUpdate must have kSCUP tag.";
 784     return QUIC_INVALID_CRYPTO_MESSAGE_TYPE;
 785   }
 786
 787   return CacheNewServerConfig(server_config_update, now,
 788                               out_params->cached_certs, cached, error_details);
 789 }
 790
 791 ProofVerifier* QuicCryptoClientConfig::proof_verifier() const {
 792   return proof_verifier_.get();
 793 }
 794
 795 void QuicCryptoClientConfig::SetProofVerifier(ProofVerifier* verifier) {
 796   proof_verifier_.reset(verifier);
 797 }
 798
 799 ChannelIDSource* QuicCryptoClientConfig::channel_id_source() const {
 800   return channel_id_source_.get();
 801 }
 802
 803 void QuicCryptoClientConfig::SetChannelIDSource(ChannelIDSource* source) {
 804   channel_id_source_.reset(source);
 805 }
 806
 807 void QuicCryptoClientConfig::InitializeFrom(
 808     const QuicServerId& server_id,
 809     const QuicServerId& canonical_server_id,
 810     QuicCryptoClientConfig* canonical_crypto_config) {
 811   CachedState* canonical_cached =
 812       canonical_crypto_config->LookupOrCreate(canonical_server_id);
 813   if (!canonical_cached->proof_valid()) {
 814     return;
 815   }
 816   CachedState* cached = LookupOrCreate(server_id);
 817   cached->InitializeFrom(*canonical_cached);
 818 }
 819
 820 void QuicCryptoClientConfig::AddCanonicalSuffix(const string& suffix) {
 821   canonical_suffixes_.push_back(suffix);
 822 }
 823
 824 void QuicCryptoClientConfig::PreferAesGcm() {
 825   DCHECK(!aead.empty());
 826   if (aead.size() <= 1) {
 827     return;
 828   }
 829   QuicTagVector::iterator pos = std::find(aead.begin(), aead.end(), kAESG);
 830   if (pos != aead.end()) {
 831     aead.erase(pos);
 832     aead.insert(aead.begin(), kAESG);
 833   }
 834 }
 835
 836 void QuicCryptoClientConfig::DisableEcdsa() {
 837   disable_ecdsa_ = true;
 838 }
 839
 840 bool QuicCryptoClientConfig::PopulateFromCanonicalConfig(
 841     const QuicServerId& server_id,
 842     CachedState* server_state) {
 843   DCHECK(server_state->IsEmpty());
 844   size_t i = 0;
 845   for (; i < canonical_suffixes_.size(); ++i) {
 846     if (EndsWith(server_id.host(), canonical_suffixes_[i], false)) {
 847       break;
 848     }
 849   }
 850   if (i == canonical_suffixes_.size()) {
 851     return false;
 852   }
 853
 854   QuicServerId suffix_server_id(canonical_suffixes_[i], server_id.port(),
 855                                 server_id.is_https(),
 856                                 server_id.privacy_mode());
 857   if (!ContainsKey(canonical_server_map_, suffix_server_id)) {
 858     // This is the first host we've seen which matches the suffix, so make it
 859     // canonical.
 860     canonical_server_map_[suffix_server_id] = server_id;
 861     return false;
 862   }
 863
 864   const QuicServerId& canonical_server_id =
 865       canonical_server_map_[suffix_server_id];
 866   CachedState* canonical_state = cached_states_[canonical_server_id];
 867   if (!canonical_state->proof_valid()) {
 868     return false;
 869   }
 870
 871   // Update canonical version to point at the "most recent" entry.
 872   canonical_server_map_[suffix_server_id] = server_id;
 873
 874   server_state->InitializeFrom(*canonical_state);
 875   return true;
 876 }
 877
 878 }  // namespace net