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_macros.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::queue;
  28 using std::vector;
  29
  30 namespace net {
  31
  32 namespace {
  33
  34 // Tracks the reason (the state of the server config) for sending inchoate
  35 // ClientHello to the server.
  36 void RecordInchoateClientHelloReason(
  37     QuicCryptoClientConfig::CachedState::ServerConfigState state) {
  38   UMA_HISTOGRAM_ENUMERATION(
  39       "Net.QuicInchoateClientHelloReason", state,
  40       QuicCryptoClientConfig::CachedState::SERVER_CONFIG_COUNT);
  41 }
  42
  43 // Tracks the state of the QUIC server information loaded from the disk cache.
  44 void RecordDiskCacheServerConfigState(
  45     QuicCryptoClientConfig::CachedState::ServerConfigState state) {
  46   UMA_HISTOGRAM_ENUMERATION(
  47       "Net.QuicServerInfo.DiskCacheState", state,
  48       QuicCryptoClientConfig::CachedState::SERVER_CONFIG_COUNT);
  49 }
  50
  51 }  // namespace
  52
  53 QuicCryptoClientConfig::QuicCryptoClientConfig()
  54     : disable_ecdsa_(false) {
  55   SetDefaults();
  56 }
  57
  58 QuicCryptoClientConfig::~QuicCryptoClientConfig() {
  59   STLDeleteValues(&cached_states_);
  60 }
  61
  62 QuicCryptoClientConfig::CachedState::CachedState()
  63     : server_config_valid_(false),
  64       generation_counter_(0) {}
  65
  66 QuicCryptoClientConfig::CachedState::~CachedState() {}
  67
  68 bool QuicCryptoClientConfig::CachedState::IsComplete(QuicWallTime now) const {
  69   if (server_config_.empty()) {
  70     RecordInchoateClientHelloReason(SERVER_CONFIG_EMPTY);
  71     return false;
  72   }
  73
  74   if (!server_config_valid_) {
  75     RecordInchoateClientHelloReason(SERVER_CONFIG_INVALID);
  76     return false;
  77   }
  78
  79   const CryptoHandshakeMessage* scfg = GetServerConfig();
  80   if (!scfg) {
  81     // Should be impossible short of cache corruption.
  82     DCHECK(false);
  83     RecordInchoateClientHelloReason(SERVER_CONFIG_CORRUPTED);
  84     return false;
  85   }
  86
  87   uint64 expiry_seconds;
  88   if (scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
  89     RecordInchoateClientHelloReason(SERVER_CONFIG_INVALID_EXPIRY);
  90     return false;
  91   }
  92   if (now.ToUNIXSeconds() >= expiry_seconds) {
  93     UMA_HISTOGRAM_CUSTOM_TIMES(
  94         "Net.QuicClientHelloServerConfig.InvalidDuration",
  95         base::TimeDelta::FromSeconds(now.ToUNIXSeconds() - expiry_seconds),
  96         base::TimeDelta::FromMinutes(1), base::TimeDelta::FromDays(20), 50);
  97     RecordInchoateClientHelloReason(SERVER_CONFIG_EXPIRED);
  98     return false;
  99   }
 100
 101   return true;
 102 }
 103
 104 bool QuicCryptoClientConfig::CachedState::IsEmpty() const {
 105   return server_config_.empty();
 106 }
 107
 108 const CryptoHandshakeMessage*
 109 QuicCryptoClientConfig::CachedState::GetServerConfig() const {
 110   if (server_config_.empty()) {
 111     return nullptr;
 112   }
 113
 114   if (!scfg_.get()) {
 115     scfg_.reset(CryptoFramer::ParseMessage(server_config_));
 116     DCHECK(scfg_.get());
 117   }
 118   return scfg_.get();
 119 }
 120
 121 void QuicCryptoClientConfig::CachedState::add_server_designated_connection_id(
 122     QuicConnectionId connection_id) {
 123   server_designated_connection_ids_.push(connection_id);
 124 }
 125
 126 bool QuicCryptoClientConfig::CachedState::has_server_designated_connection_id()
 127     const {
 128   return !server_designated_connection_ids_.empty();
 129 }
 130
 131 void QuicCryptoClientConfig::CachedState::add_server_nonce(
 132     const string& server_nonce) {
 133   server_nonces_.push(server_nonce);
 134 }
 135
 136 bool QuicCryptoClientConfig::CachedState::has_server_nonce() const {
 137   return !server_nonces_.empty();
 138 }
 139
 140 QuicCryptoClientConfig::CachedState::ServerConfigState
 141 QuicCryptoClientConfig::CachedState::SetServerConfig(
 142     StringPiece server_config, QuicWallTime now, string* error_details) {
 143   const bool matches_existing = server_config == server_config_;
 144
 145   // Even if the new server config matches the existing one, we still wish to
 146   // reject it if it has expired.
 147   scoped_ptr<CryptoHandshakeMessage> new_scfg_storage;
 148   const CryptoHandshakeMessage* new_scfg;
 149
 150   if (!matches_existing) {
 151     new_scfg_storage.reset(CryptoFramer::ParseMessage(server_config));
 152     new_scfg = new_scfg_storage.get();
 153   } else {
 154     new_scfg = GetServerConfig();
 155   }
 156
 157   if (!new_scfg) {
 158     *error_details = "SCFG invalid";
 159     return SERVER_CONFIG_INVALID;
 160   }
 161
 162   uint64 expiry_seconds;
 163   if (new_scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
 164     *error_details = "SCFG missing EXPY";
 165     return SERVER_CONFIG_INVALID_EXPIRY;
 166   }
 167
 168   if (now.ToUNIXSeconds() >= expiry_seconds) {
 169     *error_details = "SCFG has expired";
 170     return SERVER_CONFIG_EXPIRED;
 171   }
 172
 173   if (!matches_existing) {
 174     server_config_ = server_config.as_string();
 175     SetProofInvalid();
 176     scfg_.reset(new_scfg_storage.release());
 177   }
 178   return SERVER_CONFIG_VALID;
 179 }
 180
 181 void QuicCryptoClientConfig::CachedState::InvalidateServerConfig() {
 182   server_config_.clear();
 183   scfg_.reset();
 184   SetProofInvalid();
 185   queue<QuicConnectionId> empty_queue;
 186   swap(server_designated_connection_ids_, empty_queue);
 187 }
 188
 189 void QuicCryptoClientConfig::CachedState::SetProof(const vector<string>& certs,
 190                                                    StringPiece signature) {
 191   bool has_changed =
 192       signature != server_config_sig_ || certs_.size() != certs.size();
 193
 194   if (!has_changed) {
 195     for (size_t i = 0; i < certs_.size(); i++) {
 196       if (certs_[i] != certs[i]) {
 197         has_changed = true;
 198         break;
 199       }
 200     }
 201   }
 202
 203   if (!has_changed) {
 204     return;
 205   }
 206
 207   // If the proof has changed then it needs to be revalidated.
 208   SetProofInvalid();
 209   certs_ = certs;
 210   server_config_sig_ = signature.as_string();
 211 }
 212
 213 void QuicCryptoClientConfig::CachedState::Clear() {
 214   server_config_.clear();
 215   source_address_token_.clear();
 216   certs_.clear();
 217   server_config_sig_.clear();
 218   server_config_valid_ = false;
 219   proof_verify_details_.reset();
 220   scfg_.reset();
 221   ++generation_counter_;
 222   queue<QuicConnectionId> empty_queue;
 223   swap(server_designated_connection_ids_, empty_queue);
 224 }
 225
 226 void QuicCryptoClientConfig::CachedState::ClearProof() {
 227   SetProofInvalid();
 228   certs_.clear();
 229   server_config_sig_.clear();
 230 }
 231
 232 void QuicCryptoClientConfig::CachedState::SetProofValid() {
 233   server_config_valid_ = true;
 234 }
 235
 236 void QuicCryptoClientConfig::CachedState::SetProofInvalid() {
 237   server_config_valid_ = false;
 238   ++generation_counter_;
 239 }
 240
 241 bool QuicCryptoClientConfig::CachedState::Initialize(
 242     StringPiece server_config,
 243     StringPiece source_address_token,
 244     const vector<string>& certs,
 245     StringPiece signature,
 246     QuicWallTime now) {
 247   DCHECK(server_config_.empty());
 248
 249   if (server_config.empty()) {
 250     RecordDiskCacheServerConfigState(SERVER_CONFIG_EMPTY);
 251     return false;
 252   }
 253
 254   string error_details;
 255   ServerConfigState state = SetServerConfig(server_config, now,
 256                                             &error_details);
 257   RecordDiskCacheServerConfigState(state);
 258   if (state != SERVER_CONFIG_VALID) {
 259     DVLOG(1) << "SetServerConfig failed with " << error_details;
 260     return false;
 261   }
 262
 263   signature.CopyToString(&server_config_sig_);
 264   source_address_token.CopyToString(&source_address_token_);
 265   certs_ = certs;
 266   return true;
 267 }
 268
 269 const string& QuicCryptoClientConfig::CachedState::server_config() const {
 270   return server_config_;
 271 }
 272
 273 const string&
 274 QuicCryptoClientConfig::CachedState::source_address_token() const {
 275   return source_address_token_;
 276 }
 277
 278 const vector<string>& QuicCryptoClientConfig::CachedState::certs() const {
 279   return certs_;
 280 }
 281
 282 const string& QuicCryptoClientConfig::CachedState::signature() const {
 283   return server_config_sig_;
 284 }
 285
 286 bool QuicCryptoClientConfig::CachedState::proof_valid() const {
 287   return server_config_valid_;
 288 }
 289
 290 uint64 QuicCryptoClientConfig::CachedState::generation_counter() const {
 291   return generation_counter_;
 292 }
 293
 294 const ProofVerifyDetails*
 295 QuicCryptoClientConfig::CachedState::proof_verify_details() const {
 296   return proof_verify_details_.get();
 297 }
 298
 299 void QuicCryptoClientConfig::CachedState::set_source_address_token(
 300     StringPiece token) {
 301   source_address_token_ = token.as_string();
 302 }
 303
 304 void QuicCryptoClientConfig::CachedState::SetProofVerifyDetails(
 305     ProofVerifyDetails* details) {
 306   proof_verify_details_.reset(details);
 307 }
 308
 309 void QuicCryptoClientConfig::CachedState::InitializeFrom(
 310     const QuicCryptoClientConfig::CachedState& other) {
 311   DCHECK(server_config_.empty());
 312   DCHECK(!server_config_valid_);
 313   server_config_ = other.server_config_;
 314   source_address_token_ = other.source_address_token_;
 315   certs_ = other.certs_;
 316   server_config_sig_ = other.server_config_sig_;
 317   server_config_valid_ = other.server_config_valid_;
 318   server_designated_connection_ids_ = other.server_designated_connection_ids_;
 319   if (other.proof_verify_details_.get() != nullptr) {
 320     proof_verify_details_.reset(other.proof_verify_details_->Clone());
 321   }
 322   ++generation_counter_;
 323 }
 324
 325 QuicConnectionId
 326 QuicCryptoClientConfig::CachedState::GetNextServerDesignatedConnectionId() {
 327   if (server_designated_connection_ids_.empty()) {
 328     LOG(DFATAL)
 329         << "Attempting to consume a connection id that was never designated.";
 330     return 0;
 331   }
 332   const QuicConnectionId next_id = server_designated_connection_ids_.front();
 333   server_designated_connection_ids_.pop();
 334   return next_id;
 335 }
 336
 337 string QuicCryptoClientConfig::CachedState::GetNextServerNonce() {
 338   if (server_nonces_.empty()) {
 339     LOG(DFATAL)
 340         << "Attempting to consume a server nonce that was never designated.";
 341     return "";
 342   }
 343   const string server_nonce = server_nonces_.front();
 344   server_nonces_.pop();
 345   return server_nonce;
 346 }
 347
 348 void QuicCryptoClientConfig::SetDefaults() {
 349   // Key exchange methods.
 350   kexs.resize(2);
 351   kexs[0] = kC255;
 352   kexs[1] = kP256;
 353
 354   // Authenticated encryption algorithms. Prefer ChaCha20 by default.
 355   aead.clear();
 356   if (ChaCha20Poly1305Encrypter::IsSupported()) {
 357     aead.push_back(kCC12);
 358   }
 359   aead.push_back(kAESG);
 360
 361   disable_ecdsa_ = false;
 362 }
 363
 364 QuicCryptoClientConfig::CachedState* QuicCryptoClientConfig::LookupOrCreate(
 365     const QuicServerId& server_id) {
 366   CachedStateMap::const_iterator it = cached_states_.find(server_id);
 367   if (it != cached_states_.end()) {
 368     return it->second;
 369   }
 370
 371   CachedState* cached = new CachedState;
 372   cached_states_.insert(std::make_pair(server_id, cached));
 373   bool cache_populated = PopulateFromCanonicalConfig(server_id, cached);
 374   UMA_HISTOGRAM_BOOLEAN(
 375       "Net.QuicCryptoClientConfig.PopulatedFromCanonicalConfig",
 376       cache_populated);
 377   return cached;
 378 }
 379
 380 void QuicCryptoClientConfig::ClearCachedStates() {
 381   for (CachedStateMap::const_iterator it = cached_states_.begin();
 382        it != cached_states_.end(); ++it) {
 383     it->second->Clear();
 384   }
 385 }
 386
 387 void QuicCryptoClientConfig::FillInchoateClientHello(
 388     const QuicServerId& server_id,
 389     const QuicVersion preferred_version,
 390     const CachedState* cached,
 391     QuicCryptoNegotiatedParameters* out_params,
 392     CryptoHandshakeMessage* out) const {
 393   out->set_tag(kCHLO);
 394   out->set_minimum_size(kClientHelloMinimumSize);
 395
 396   // Server name indication. We only send SNI if it's a valid domain name, as
 397   // per the spec.
 398   if (CryptoUtils::IsValidSNI(server_id.host())) {
 399     out->SetStringPiece(kSNI, server_id.host());
 400   }
 401   out->SetValue(kVER, QuicVersionToQuicTag(preferred_version));
 402
 403   if (!user_agent_id_.empty()) {
 404     out->SetStringPiece(kUAID, user_agent_id_);
 405   }
 406
 407   if (!cached->source_address_token().empty()) {
 408     out->SetStringPiece(kSourceAddressTokenTag, cached->source_address_token());
 409   }
 410
 411   if (server_id.is_https()) {
 412     if (disable_ecdsa_) {
 413       out->SetTaglist(kPDMD, kX59R, 0);
 414     } else {
 415       out->SetTaglist(kPDMD, kX509, 0);
 416     }
 417   }
 418
 419   if (common_cert_sets) {
 420     out->SetStringPiece(kCCS, common_cert_sets->GetCommonHashes());
 421   }
 422
 423   const vector<string>& certs = cached->certs();
 424   // We save |certs| in the QuicCryptoNegotiatedParameters so that, if the
 425   // client config is being used for multiple connections, another connection
 426   // doesn't update the cached certificates and cause us to be unable to
 427   // process the server's compressed certificate chain.
 428   out_params->cached_certs = certs;
 429   if (!certs.empty()) {
 430     vector<uint64> hashes;
 431     hashes.reserve(certs.size());
 432     for (vector<string>::const_iterator i = certs.begin();
 433          i != certs.end(); ++i) {
 434       hashes.push_back(QuicUtils::FNV1a_64_Hash(i->data(), i->size()));
 435     }
 436     out->SetVector(kCCRT, hashes);
 437   }
 438 }
 439
 440 QuicErrorCode QuicCryptoClientConfig::FillClientHello(
 441     const QuicServerId& server_id,
 442     QuicConnectionId connection_id,
 443     const QuicVersion preferred_version,
 444     const CachedState* cached,
 445     QuicWallTime now,
 446     QuicRandom* rand,
 447     const ChannelIDKey* channel_id_key,
 448     QuicCryptoNegotiatedParameters* out_params,
 449     CryptoHandshakeMessage* out,
 450     string* error_details) const {
 451   DCHECK(error_details != nullptr);
 452
 453   FillInchoateClientHello(server_id, preferred_version, cached,
 454                           out_params, out);
 455
 456   const CryptoHandshakeMessage* scfg = cached->GetServerConfig();
 457   if (!scfg) {
 458     // This should never happen as our caller should have checked
 459     // cached->IsComplete() before calling this function.
 460     *error_details = "Handshake not ready";
 461     return QUIC_CRYPTO_INTERNAL_ERROR;
 462   }
 463
 464   StringPiece scid;
 465   if (!scfg->GetStringPiece(kSCID, &scid)) {
 466     *error_details = "SCFG missing SCID";
 467     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 468   }
 469   out->SetStringPiece(kSCID, scid);
 470
 471   const QuicTag* their_aeads;
 472   const QuicTag* their_key_exchanges;
 473   size_t num_their_aeads, num_their_key_exchanges;
 474   if (scfg->GetTaglist(kAEAD, &their_aeads,
 475                        &num_their_aeads) != QUIC_NO_ERROR ||
 476       scfg->GetTaglist(kKEXS, &their_key_exchanges,
 477                        &num_their_key_exchanges) != QUIC_NO_ERROR) {
 478     *error_details = "Missing AEAD or KEXS";
 479     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 480   }
 481
 482   // AEAD: the work loads on the client and server are symmetric. Since the
 483   // client is more likely to be CPU-constrained, break the tie by favoring
 484   // the client's preference.
 485   // Key exchange: the client does more work than the server, so favor the
 486   // client's preference.
 487   size_t key_exchange_index;
 488   if (!QuicUtils::FindMutualTag(
 489           aead, their_aeads, num_their_aeads, QuicUtils::LOCAL_PRIORITY,
 490           &out_params->aead, nullptr) ||
 491       !QuicUtils::FindMutualTag(
 492           kexs, their_key_exchanges, num_their_key_exchanges,
 493           QuicUtils::LOCAL_PRIORITY, &out_params->key_exchange,
 494           &key_exchange_index)) {
 495     *error_details = "Unsupported AEAD or KEXS";
 496     return QUIC_CRYPTO_NO_SUPPORT;
 497   }
 498   out->SetTaglist(kAEAD, out_params->aead, 0);
 499   out->SetTaglist(kKEXS, out_params->key_exchange, 0);
 500
 501   StringPiece public_value;
 502   if (scfg->GetNthValue24(kPUBS, key_exchange_index, &public_value) !=
 503           QUIC_NO_ERROR) {
 504     *error_details = "Missing public value";
 505     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 506   }
 507
 508   StringPiece orbit;
 509   if (!scfg->GetStringPiece(kORBT, &orbit) || orbit.size() != kOrbitSize) {
 510     *error_details = "SCFG missing OBIT";
 511     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 512   }
 513
 514   CryptoUtils::GenerateNonce(now, rand, orbit, &out_params->client_nonce);
 515   out->SetStringPiece(kNONC, out_params->client_nonce);
 516   if (!out_params->server_nonce.empty()) {
 517     out->SetStringPiece(kServerNonceTag, out_params->server_nonce);
 518   }
 519
 520   switch (out_params->key_exchange) {
 521     case kC255:
 522       out_params->client_key_exchange.reset(Curve25519KeyExchange::New(
 523           Curve25519KeyExchange::NewPrivateKey(rand)));
 524       break;
 525     case kP256:
 526       out_params->client_key_exchange.reset(P256KeyExchange::New(
 527           P256KeyExchange::NewPrivateKey()));
 528       break;
 529     default:
 530       DCHECK(false);
 531       *error_details = "Configured to support an unknown key exchange";
 532       return QUIC_CRYPTO_INTERNAL_ERROR;
 533   }
 534
 535   if (!out_params->client_key_exchange->CalculateSharedKey(
 536           public_value, &out_params->initial_premaster_secret)) {
 537     *error_details = "Key exchange failure";
 538     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 539   }
 540   out->SetStringPiece(kPUBS, out_params->client_key_exchange->public_value());
 541
 542   if (channel_id_key) {
 543     // In order to calculate the encryption key for the CETV block we need to
 544     // serialise the client hello as it currently is (i.e. without the CETV
 545     // block). For this, the client hello is serialized without padding.
 546     const size_t orig_min_size = out->minimum_size();
 547     out->set_minimum_size(0);
 548
 549     CryptoHandshakeMessage cetv;
 550     cetv.set_tag(kCETV);
 551
 552     string hkdf_input;
 553     const QuicData& client_hello_serialized = out->GetSerialized();
 554     hkdf_input.append(QuicCryptoConfig::kCETVLabel,
 555                       strlen(QuicCryptoConfig::kCETVLabel) + 1);
 556     hkdf_input.append(reinterpret_cast<char*>(&connection_id),
 557                       sizeof(connection_id));
 558     hkdf_input.append(client_hello_serialized.data(),
 559                       client_hello_serialized.length());
 560     hkdf_input.append(cached->server_config());
 561
 562     string key = channel_id_key->SerializeKey();
 563     string signature;
 564     if (!channel_id_key->Sign(hkdf_input, &signature)) {
 565       *error_details = "Channel ID signature failed";
 566       return QUIC_INVALID_CHANNEL_ID_SIGNATURE;
 567     }
 568
 569     cetv.SetStringPiece(kCIDK, key);
 570     cetv.SetStringPiece(kCIDS, signature);
 571
 572     CrypterPair crypters;
 573     if (!CryptoUtils::DeriveKeys(
 574             out_params->initial_premaster_secret, out_params->aead,
 575             out_params->client_nonce, out_params->server_nonce, hkdf_input,
 576             Perspective::IS_CLIENT, &crypters, nullptr /* subkey secret */)) {
 577       *error_details = "Symmetric key setup failed";
 578       return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 579     }
 580
 581     const QuicData& cetv_plaintext = cetv.GetSerialized();
 582     const size_t encrypted_len =
 583         crypters.encrypter->GetCiphertextSize(cetv_plaintext.length());
 584     scoped_ptr<char[]> output(new char[encrypted_len]);
 585     size_t output_size = 0;
 586     if (!crypters.encrypter->EncryptPacket(
 587             0 /* packet number */, StringPiece() /* associated data */,
 588             cetv_plaintext.AsStringPiece(), output.get(), &output_size,
 589             encrypted_len)) {
 590       *error_details = "Packet encryption failed";
 591       return QUIC_ENCRYPTION_FAILURE;
 592     }
 593
 594     out->SetStringPiece(kCETV, StringPiece(output.get(), output_size));
 595     out->MarkDirty();
 596
 597     out->set_minimum_size(orig_min_size);
 598   }
 599
 600   // Derive the symmetric keys and set up the encrypters and decrypters.
 601   // Set the following members of out_params:
 602   //   out_params->hkdf_input_suffix
 603   //   out_params->initial_crypters
 604   out_params->hkdf_input_suffix.clear();
 605   out_params->hkdf_input_suffix.append(reinterpret_cast<char*>(&connection_id),
 606                                        sizeof(connection_id));
 607   const QuicData& client_hello_serialized = out->GetSerialized();
 608   out_params->hkdf_input_suffix.append(client_hello_serialized.data(),
 609                                        client_hello_serialized.length());
 610   out_params->hkdf_input_suffix.append(cached->server_config());
 611
 612   string hkdf_input;
 613   const size_t label_len = strlen(QuicCryptoConfig::kInitialLabel) + 1;
 614   hkdf_input.reserve(label_len + out_params->hkdf_input_suffix.size());
 615   hkdf_input.append(QuicCryptoConfig::kInitialLabel, label_len);
 616   hkdf_input.append(out_params->hkdf_input_suffix);
 617
 618   if (!CryptoUtils::DeriveKeys(
 619           out_params->initial_premaster_secret, out_params->aead,
 620           out_params->client_nonce, out_params->server_nonce, hkdf_input,
 621           Perspective::IS_CLIENT, &out_params->initial_crypters,
 622           nullptr /* subkey secret */)) {
 623     *error_details = "Symmetric key setup failed";
 624     return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 625   }
 626
 627   return QUIC_NO_ERROR;
 628 }
 629
 630 QuicErrorCode QuicCryptoClientConfig::CacheNewServerConfig(
 631     const CryptoHandshakeMessage& message,
 632     QuicWallTime now,
 633     const vector<string>& cached_certs,
 634     CachedState* cached,
 635     string* error_details) {
 636   DCHECK(error_details != nullptr);
 637
 638   StringPiece scfg;
 639   if (!message.GetStringPiece(kSCFG, &scfg)) {
 640     *error_details = "Missing SCFG";
 641     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 642   }
 643
 644   CachedState::ServerConfigState state = cached->SetServerConfig(
 645       scfg, now, error_details);
 646   if (state == CachedState::SERVER_CONFIG_EXPIRED) {
 647     return QUIC_CRYPTO_SERVER_CONFIG_EXPIRED;
 648   }
 649   // TODO(rtenneti): Return more specific error code than returning
 650   // QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER.
 651   if (state != CachedState::SERVER_CONFIG_VALID) {
 652     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 653   }
 654
 655   StringPiece token;
 656   if (message.GetStringPiece(kSourceAddressTokenTag, &token)) {
 657     cached->set_source_address_token(token);
 658   }
 659
 660   StringPiece proof, cert_bytes;
 661   bool has_proof = message.GetStringPiece(kPROF, &proof);
 662   bool has_cert = message.GetStringPiece(kCertificateTag, &cert_bytes);
 663   if (has_proof && has_cert) {
 664     vector<string> certs;
 665     if (!CertCompressor::DecompressChain(cert_bytes, cached_certs,
 666                                          common_cert_sets, &certs)) {
 667       *error_details = "Certificate data invalid";
 668       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 669     }
 670
 671     cached->SetProof(certs, proof);
 672   } else {
 673     if (proof_verifier() != nullptr) {
 674       // Secure QUIC: clear existing proof as we have been sent a new SCFG
 675       // without matching proof/certs.
 676       cached->ClearProof();
 677     }
 678
 679     if (has_proof && !has_cert) {
 680       *error_details = "Certificate missing";
 681       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 682     }
 683
 684     if (!has_proof && has_cert) {
 685       *error_details = "Proof missing";
 686       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 687     }
 688   }
 689
 690   return QUIC_NO_ERROR;
 691 }
 692
 693 QuicErrorCode QuicCryptoClientConfig::ProcessRejection(
 694     const CryptoHandshakeMessage& rej,
 695     QuicWallTime now,
 696     CachedState* cached,
 697     bool is_https,
 698     QuicCryptoNegotiatedParameters* out_params,
 699     string* error_details) {
 700   DCHECK(error_details != nullptr);
 701
 702   if ((rej.tag() != kREJ) && (rej.tag() != kSREJ)) {
 703     *error_details = "Message is not REJ or SREJ";
 704     return QUIC_CRYPTO_INTERNAL_ERROR;
 705   }
 706
 707   QuicErrorCode error = CacheNewServerConfig(rej, now, out_params->cached_certs,
 708                                              cached, error_details);
 709   if (error != QUIC_NO_ERROR) {
 710     return error;
 711   }
 712
 713   StringPiece nonce;
 714   if (rej.GetStringPiece(kServerNonceTag, &nonce)) {
 715     out_params->server_nonce = nonce.as_string();
 716   }
 717
 718   const uint32* reject_reasons;
 719   size_t num_reject_reasons;
 720   static_assert(sizeof(QuicTag) == sizeof(uint32), "header out of sync");
 721   if (rej.GetTaglist(kRREJ, &reject_reasons,
 722                      &num_reject_reasons) == QUIC_NO_ERROR) {
 723     uint32 packed_error = 0;
 724     for (size_t i = 0; i < num_reject_reasons; ++i) {
 725       // HANDSHAKE_OK is 0 and don't report that as error.
 726       if (reject_reasons[i] == HANDSHAKE_OK || reject_reasons[i] >= 32) {
 727         continue;
 728       }
 729       HandshakeFailureReason reason =
 730           static_cast<HandshakeFailureReason>(reject_reasons[i]);
 731       packed_error |= 1 << (reason - 1);
 732     }
 733     DVLOG(1) << "Reasons for rejection: " << packed_error;
 734     if (is_https) {
 735       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons.Secure",
 736                                   packed_error);
 737     } else {
 738       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons.Insecure",
 739                                   packed_error);
 740     }
 741   }
 742
 743   if (rej.tag() == kSREJ) {
 744     QuicConnectionId connection_id;
 745     if (rej.GetUint64(kRCID, &connection_id) != QUIC_NO_ERROR) {
 746       *error_details = "Missing kRCID";
 747       return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 748     }
 749     cached->add_server_designated_connection_id(connection_id);
 750     if (!nonce.empty()) {
 751       cached->add_server_nonce(nonce.as_string());
 752     }
 753     return QUIC_NO_ERROR;
 754   }
 755
 756   return QUIC_NO_ERROR;
 757 }
 758
 759 QuicErrorCode QuicCryptoClientConfig::ProcessServerHello(
 760     const CryptoHandshakeMessage& server_hello,
 761     QuicConnectionId connection_id,
 762     const QuicVersionVector& negotiated_versions,
 763     CachedState* cached,
 764     QuicCryptoNegotiatedParameters* out_params,
 765     string* error_details) {
 766   DCHECK(error_details != nullptr);
 767
 768   if (server_hello.tag() != kSHLO) {
 769     *error_details = "Bad tag";
 770     return QUIC_INVALID_CRYPTO_MESSAGE_TYPE;
 771   }
 772
 773   const QuicTag* supported_version_tags;
 774   size_t num_supported_versions;
 775
 776   if (server_hello.GetTaglist(kVER, &supported_version_tags,
 777                               &num_supported_versions) != QUIC_NO_ERROR) {
 778     *error_details = "server hello missing version list";
 779     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 780   }
 781   if (!negotiated_versions.empty()) {
 782     bool mismatch = num_supported_versions != negotiated_versions.size();
 783     for (size_t i = 0; i < num_supported_versions && !mismatch; ++i) {
 784       mismatch = QuicTagToQuicVersion(supported_version_tags[i]) !=
 785           negotiated_versions[i];
 786     }
 787     // The server sent a list of supported versions, and the connection
 788     // reports that there was a version negotiation during the handshake.
 789       // Ensure that these two lists are identical.
 790     if (mismatch) {
 791       *error_details = "Downgrade attack detected";
 792       return QUIC_VERSION_NEGOTIATION_MISMATCH;
 793     }
 794   }
 795
 796   // Learn about updated source address tokens.
 797   StringPiece token;
 798   if (server_hello.GetStringPiece(kSourceAddressTokenTag, &token)) {
 799     cached->set_source_address_token(token);
 800   }
 801
 802   // TODO(agl):
 803   //   learn about updated SCFGs.
 804
 805   StringPiece public_value;
 806   if (!server_hello.GetStringPiece(kPUBS, &public_value)) {
 807     *error_details = "server hello missing forward secure public value";
 808     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 809   }
 810
 811   if (!out_params->client_key_exchange->CalculateSharedKey(
 812           public_value, &out_params->forward_secure_premaster_secret)) {
 813     *error_details = "Key exchange failure";
 814     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 815   }
 816
 817   string hkdf_input;
 818   const size_t label_len = strlen(QuicCryptoConfig::kForwardSecureLabel) + 1;
 819   hkdf_input.reserve(label_len + out_params->hkdf_input_suffix.size());
 820   hkdf_input.append(QuicCryptoConfig::kForwardSecureLabel, label_len);
 821   hkdf_input.append(out_params->hkdf_input_suffix);
 822
 823   if (!CryptoUtils::DeriveKeys(
 824           out_params->forward_secure_premaster_secret, out_params->aead,
 825           out_params->client_nonce, out_params->server_nonce, hkdf_input,
 826           Perspective::IS_CLIENT, &out_params->forward_secure_crypters,
 827           &out_params->subkey_secret)) {
 828     *error_details = "Symmetric key setup failed";
 829     return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 830   }
 831
 832   return QUIC_NO_ERROR;
 833 }
 834
 835 QuicErrorCode QuicCryptoClientConfig::ProcessServerConfigUpdate(
 836     const CryptoHandshakeMessage& server_config_update,
 837     QuicWallTime now,
 838     CachedState* cached,
 839     QuicCryptoNegotiatedParameters* out_params,
 840     string* error_details) {
 841   DCHECK(error_details != nullptr);
 842
 843   if (server_config_update.tag() != kSCUP) {
 844     *error_details = "ServerConfigUpdate must have kSCUP tag.";
 845     return QUIC_INVALID_CRYPTO_MESSAGE_TYPE;
 846   }
 847
 848   return CacheNewServerConfig(server_config_update, now,
 849                               out_params->cached_certs, cached, error_details);
 850 }
 851
 852 ProofVerifier* QuicCryptoClientConfig::proof_verifier() const {
 853   return proof_verifier_.get();
 854 }
 855
 856 void QuicCryptoClientConfig::SetProofVerifier(ProofVerifier* verifier) {
 857   proof_verifier_.reset(verifier);
 858 }
 859
 860 ChannelIDSource* QuicCryptoClientConfig::channel_id_source() const {
 861   return channel_id_source_.get();
 862 }
 863
 864 void QuicCryptoClientConfig::SetChannelIDSource(ChannelIDSource* source) {
 865   channel_id_source_.reset(source);
 866 }
 867
 868 void QuicCryptoClientConfig::InitializeFrom(
 869     const QuicServerId& server_id,
 870     const QuicServerId& canonical_server_id,
 871     QuicCryptoClientConfig* canonical_crypto_config) {
 872   CachedState* canonical_cached =
 873       canonical_crypto_config->LookupOrCreate(canonical_server_id);
 874   if (!canonical_cached->proof_valid()) {
 875     return;
 876   }
 877   CachedState* cached = LookupOrCreate(server_id);
 878   cached->InitializeFrom(*canonical_cached);
 879 }
 880
 881 void QuicCryptoClientConfig::AddCanonicalSuffix(const string& suffix) {
 882   canonical_suffixes_.push_back(suffix);
 883 }
 884
 885 void QuicCryptoClientConfig::PreferAesGcm() {
 886   DCHECK(!aead.empty());
 887   if (aead.size() <= 1) {
 888     return;
 889   }
 890   QuicTagVector::iterator pos = std::find(aead.begin(), aead.end(), kAESG);
 891   if (pos != aead.end()) {
 892     aead.erase(pos);
 893     aead.insert(aead.begin(), kAESG);
 894   }
 895 }
 896
 897 void QuicCryptoClientConfig::DisableEcdsa() {
 898   disable_ecdsa_ = true;
 899 }
 900
 901 bool QuicCryptoClientConfig::PopulateFromCanonicalConfig(
 902     const QuicServerId& server_id,
 903     CachedState* server_state) {
 904   DCHECK(server_state->IsEmpty());
 905   size_t i = 0;
 906   for (; i < canonical_suffixes_.size(); ++i) {
 907     if (base::EndsWith(server_id.host(), canonical_suffixes_[i],
 908                        base::CompareCase::INSENSITIVE_ASCII)) {
 909       break;
 910     }
 911   }
 912   if (i == canonical_suffixes_.size()) {
 913     return false;
 914   }
 915
 916   QuicServerId suffix_server_id(canonical_suffixes_[i], server_id.port(),
 917                                 server_id.is_https(),
 918                                 server_id.privacy_mode());
 919   if (!ContainsKey(canonical_server_map_, suffix_server_id)) {
 920     // This is the first host we've seen which matches the suffix, so make it
 921     // canonical.
 922     canonical_server_map_[suffix_server_id] = server_id;
 923     return false;
 924   }
 925
 926   const QuicServerId& canonical_server_id =
 927       canonical_server_map_[suffix_server_id];
 928   CachedState* canonical_state = cached_states_[canonical_server_id];
 929   if (!canonical_state->proof_valid()) {
 930     return false;
 931   }
 932
 933   // Update canonical version to point at the "most recent" entry.
 934   canonical_server_map_[suffix_server_id] = server_id;
 935
 936   server_state->InitializeFrom(*canonical_state);
 937   return true;
 938 }
 939
 940 }  // namespace net