src/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::find;
  26 using std::make_pair;
  27 using std::map;
  28 using std::string;
  29 using std::vector;
  30
  31 namespace net {
  32
  33 namespace {
  34
  35 // Tracks the reason (the state of the server config) for sending inchoate
  36 // ClientHello to the server.
  37 void RecordInchoateClientHelloReason(
  38     QuicCryptoClientConfig::CachedState::ServerConfigState state) {
  39   UMA_HISTOGRAM_ENUMERATION(
  40       "Net.QuicInchoateClientHelloReason", state,
  41       QuicCryptoClientConfig::CachedState::SERVER_CONFIG_COUNT);
  42 }
  43
  44 // Tracks the state of the QUIC server information loaded from the disk cache.
  45 void RecordDiskCacheServerConfigState(
  46     QuicCryptoClientConfig::CachedState::ServerConfigState state) {
  47   UMA_HISTOGRAM_ENUMERATION(
  48       "Net.QuicServerInfo.DiskCacheState", state,
  49       QuicCryptoClientConfig::CachedState::SERVER_CONFIG_COUNT);
  50 }
  51
  52 }  // namespace
  53
  54 QuicCryptoClientConfig::QuicCryptoClientConfig()
  55     : disable_ecdsa_(false) {
  56   SetDefaults();
  57 }
  58
  59 QuicCryptoClientConfig::~QuicCryptoClientConfig() {
  60   STLDeleteValues(&cached_states_);
  61 }
  62
  63 QuicCryptoClientConfig::CachedState::CachedState()
  64     : server_config_valid_(false),
  65       generation_counter_(0) {}
  66
  67 QuicCryptoClientConfig::CachedState::~CachedState() {}
  68
  69 bool QuicCryptoClientConfig::CachedState::IsComplete(QuicWallTime now) const {
  70   if (server_config_.empty()) {
  71     RecordInchoateClientHelloReason(SERVER_CONFIG_EMPTY);
  72     return false;
  73   }
  74
  75   if (!server_config_valid_) {
  76     RecordInchoateClientHelloReason(SERVER_CONFIG_INVALID);
  77     return false;
  78   }
  79
  80   const CryptoHandshakeMessage* scfg = GetServerConfig();
  81   if (!scfg) {
  82     // Should be impossible short of cache corruption.
  83     DCHECK(false);
  84     RecordInchoateClientHelloReason(SERVER_CONFIG_CORRUPTED);
  85     return false;
  86   }
  87
  88   uint64 expiry_seconds;
  89   if (scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
  90     RecordInchoateClientHelloReason(SERVER_CONFIG_INVALID_EXPIRY);
  91     return false;
  92   }
  93   if (now.ToUNIXSeconds() >= expiry_seconds) {
  94     UMA_HISTOGRAM_CUSTOM_TIMES(
  95         "Net.QuicClientHelloServerConfig.InvalidDuration",
  96         base::TimeDelta::FromSeconds(now.ToUNIXSeconds() - expiry_seconds),
  97         base::TimeDelta::FromMinutes(1), base::TimeDelta::FromDays(20), 50);
  98     RecordInchoateClientHelloReason(SERVER_CONFIG_EXPIRED);
  99     return false;
 100   }
 101
 102   return true;
 103 }
 104
 105 bool QuicCryptoClientConfig::CachedState::IsEmpty() const {
 106   return server_config_.empty();
 107 }
 108
 109 const CryptoHandshakeMessage*
 110 QuicCryptoClientConfig::CachedState::GetServerConfig() const {
 111   if (server_config_.empty()) {
 112     return nullptr;
 113   }
 114
 115   if (!scfg_.get()) {
 116     scfg_.reset(CryptoFramer::ParseMessage(server_config_));
 117     DCHECK(scfg_.get());
 118   }
 119   return scfg_.get();
 120 }
 121
 122 QuicCryptoClientConfig::CachedState::ServerConfigState
 123 QuicCryptoClientConfig::CachedState::SetServerConfig(
 124     StringPiece server_config, QuicWallTime now, string* error_details) {
 125   const bool matches_existing = server_config == server_config_;
 126
 127   // Even if the new server config matches the existing one, we still wish to
 128   // reject it if it has expired.
 129   scoped_ptr<CryptoHandshakeMessage> new_scfg_storage;
 130   const CryptoHandshakeMessage* new_scfg;
 131
 132   if (!matches_existing) {
 133     new_scfg_storage.reset(CryptoFramer::ParseMessage(server_config));
 134     new_scfg = new_scfg_storage.get();
 135   } else {
 136     new_scfg = GetServerConfig();
 137   }
 138
 139   if (!new_scfg) {
 140     *error_details = "SCFG invalid";
 141     return SERVER_CONFIG_INVALID;
 142   }
 143
 144   uint64 expiry_seconds;
 145   if (new_scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
 146     *error_details = "SCFG missing EXPY";
 147     return SERVER_CONFIG_INVALID_EXPIRY;
 148   }
 149
 150   if (now.ToUNIXSeconds() >= expiry_seconds) {
 151     *error_details = "SCFG has expired";
 152     return SERVER_CONFIG_EXPIRED;
 153   }
 154
 155   if (!matches_existing) {
 156     server_config_ = server_config.as_string();
 157     SetProofInvalid();
 158     scfg_.reset(new_scfg_storage.release());
 159   }
 160   return SERVER_CONFIG_VALID;
 161 }
 162
 163 void QuicCryptoClientConfig::CachedState::InvalidateServerConfig() {
 164   server_config_.clear();
 165   scfg_.reset();
 166   SetProofInvalid();
 167 }
 168
 169 void QuicCryptoClientConfig::CachedState::SetProof(const vector<string>& certs,
 170                                                    StringPiece signature) {
 171   bool has_changed =
 172       signature != server_config_sig_ || certs_.size() != certs.size();
 173
 174   if (!has_changed) {
 175     for (size_t i = 0; i < certs_.size(); i++) {
 176       if (certs_[i] != certs[i]) {
 177         has_changed = true;
 178         break;
 179       }
 180     }
 181   }
 182
 183   if (!has_changed) {
 184     return;
 185   }
 186
 187   // If the proof has changed then it needs to be revalidated.
 188   SetProofInvalid();
 189   certs_ = certs;
 190   server_config_sig_ = signature.as_string();
 191 }
 192
 193 void QuicCryptoClientConfig::CachedState::Clear() {
 194   server_config_.clear();
 195   source_address_token_.clear();
 196   certs_.clear();
 197   server_config_sig_.clear();
 198   server_config_valid_ = false;
 199   proof_verify_details_.reset();
 200   scfg_.reset();
 201   ++generation_counter_;
 202 }
 203
 204 void QuicCryptoClientConfig::CachedState::ClearProof() {
 205   SetProofInvalid();
 206   certs_.clear();
 207   server_config_sig_.clear();
 208 }
 209
 210 void QuicCryptoClientConfig::CachedState::SetProofValid() {
 211   server_config_valid_ = true;
 212 }
 213
 214 void QuicCryptoClientConfig::CachedState::SetProofInvalid() {
 215   server_config_valid_ = false;
 216   ++generation_counter_;
 217 }
 218
 219 bool QuicCryptoClientConfig::CachedState::Initialize(
 220     StringPiece server_config,
 221     StringPiece source_address_token,
 222     const vector<string>& certs,
 223     StringPiece signature,
 224     QuicWallTime now) {
 225   DCHECK(server_config_.empty());
 226
 227   if (server_config.empty()) {
 228     RecordDiskCacheServerConfigState(SERVER_CONFIG_EMPTY);
 229     return false;
 230   }
 231
 232   string error_details;
 233   ServerConfigState state = SetServerConfig(server_config, now,
 234                                             &error_details);
 235   RecordDiskCacheServerConfigState(state);
 236   if (state != SERVER_CONFIG_VALID) {
 237     DVLOG(1) << "SetServerConfig failed with " << error_details;
 238     return false;
 239   }
 240
 241   signature.CopyToString(&server_config_sig_);
 242   source_address_token.CopyToString(&source_address_token_);
 243   certs_ = certs;
 244   return true;
 245 }
 246
 247 const string& QuicCryptoClientConfig::CachedState::server_config() const {
 248   return server_config_;
 249 }
 250
 251 const string&
 252 QuicCryptoClientConfig::CachedState::source_address_token() const {
 253   return source_address_token_;
 254 }
 255
 256 const vector<string>& QuicCryptoClientConfig::CachedState::certs() const {
 257   return certs_;
 258 }
 259
 260 const string& QuicCryptoClientConfig::CachedState::signature() const {
 261   return server_config_sig_;
 262 }
 263
 264 bool QuicCryptoClientConfig::CachedState::proof_valid() const {
 265   return server_config_valid_;
 266 }
 267
 268 uint64 QuicCryptoClientConfig::CachedState::generation_counter() const {
 269   return generation_counter_;
 270 }
 271
 272 const ProofVerifyDetails*
 273 QuicCryptoClientConfig::CachedState::proof_verify_details() const {
 274   return proof_verify_details_.get();
 275 }
 276
 277 void QuicCryptoClientConfig::CachedState::set_source_address_token(
 278     StringPiece token) {
 279   source_address_token_ = token.as_string();
 280 }
 281
 282 void QuicCryptoClientConfig::CachedState::SetProofVerifyDetails(
 283     ProofVerifyDetails* details) {
 284   proof_verify_details_.reset(details);
 285 }
 286
 287 void QuicCryptoClientConfig::CachedState::InitializeFrom(
 288     const QuicCryptoClientConfig::CachedState& other) {
 289   DCHECK(server_config_.empty());
 290   DCHECK(!server_config_valid_);
 291   server_config_ = other.server_config_;
 292   source_address_token_ = other.source_address_token_;
 293   certs_ = other.certs_;
 294   server_config_sig_ = other.server_config_sig_;
 295   server_config_valid_ = other.server_config_valid_;
 296   if (other.proof_verify_details_.get() != nullptr) {
 297     proof_verify_details_.reset(other.proof_verify_details_->Clone());
 298   }
 299   ++generation_counter_;
 300 }
 301
 302 void QuicCryptoClientConfig::SetDefaults() {
 303   // Key exchange methods.
 304   kexs.resize(2);
 305   kexs[0] = kC255;
 306   kexs[1] = kP256;
 307
 308   // Authenticated encryption algorithms. Prefer ChaCha20 by default.
 309   aead.clear();
 310   if (ChaCha20Poly1305Encrypter::IsSupported()) {
 311     aead.push_back(kCC12);
 312   }
 313   aead.push_back(kAESG);
 314
 315   disable_ecdsa_ = false;
 316 }
 317
 318 QuicCryptoClientConfig::CachedState* QuicCryptoClientConfig::LookupOrCreate(
 319     const QuicServerId& server_id) {
 320   CachedStateMap::const_iterator it = cached_states_.find(server_id);
 321   if (it != cached_states_.end()) {
 322     return it->second;
 323   }
 324
 325   CachedState* cached = new CachedState;
 326   cached_states_.insert(make_pair(server_id, cached));
 327   bool cache_populated = PopulateFromCanonicalConfig(server_id, cached);
 328   UMA_HISTOGRAM_BOOLEAN(
 329       "Net.QuicCryptoClientConfig.PopulatedFromCanonicalConfig",
 330       cache_populated);
 331   return cached;
 332 }
 333
 334 void QuicCryptoClientConfig::ClearCachedStates() {
 335   for (CachedStateMap::const_iterator it = cached_states_.begin();
 336        it != cached_states_.end(); ++it) {
 337     it->second->Clear();
 338   }
 339 }
 340
 341 void QuicCryptoClientConfig::FillInchoateClientHello(
 342     const QuicServerId& server_id,
 343     const QuicVersion preferred_version,
 344     const CachedState* cached,
 345     QuicCryptoNegotiatedParameters* out_params,
 346     CryptoHandshakeMessage* out) const {
 347   out->set_tag(kCHLO);
 348   out->set_minimum_size(kClientHelloMinimumSize);
 349
 350   // Server name indication. We only send SNI if it's a valid domain name, as
 351   // per the spec.
 352   if (CryptoUtils::IsValidSNI(server_id.host())) {
 353     out->SetStringPiece(kSNI, server_id.host());
 354   }
 355   out->SetValue(kVER, QuicVersionToQuicTag(preferred_version));
 356
 357   if (!user_agent_id_.empty()) {
 358     out->SetStringPiece(kUAID, user_agent_id_);
 359   }
 360
 361   if (!cached->source_address_token().empty()) {
 362     out->SetStringPiece(kSourceAddressTokenTag, cached->source_address_token());
 363   }
 364
 365   if (server_id.is_https()) {
 366     if (disable_ecdsa_) {
 367       out->SetTaglist(kPDMD, kX59R, 0);
 368     } else {
 369       out->SetTaglist(kPDMD, kX509, 0);
 370     }
 371   }
 372
 373   if (common_cert_sets) {
 374     out->SetStringPiece(kCCS, common_cert_sets->GetCommonHashes());
 375   }
 376
 377   const vector<string>& certs = cached->certs();
 378   // We save |certs| in the QuicCryptoNegotiatedParameters so that, if the
 379   // client config is being used for multiple connections, another connection
 380   // doesn't update the cached certificates and cause us to be unable to
 381   // process the server's compressed certificate chain.
 382   out_params->cached_certs = certs;
 383   if (!certs.empty()) {
 384     vector<uint64> hashes;
 385     hashes.reserve(certs.size());
 386     for (vector<string>::const_iterator i = certs.begin();
 387          i != certs.end(); ++i) {
 388       hashes.push_back(QuicUtils::FNV1a_64_Hash(i->data(), i->size()));
 389     }
 390     out->SetVector(kCCRT, hashes);
 391   }
 392 }
 393
 394 QuicErrorCode QuicCryptoClientConfig::FillClientHello(
 395     const QuicServerId& server_id,
 396     QuicConnectionId connection_id,
 397     const QuicVersion preferred_version,
 398     const CachedState* cached,
 399     QuicWallTime now,
 400     QuicRandom* rand,
 401     const ChannelIDKey* channel_id_key,
 402     QuicCryptoNegotiatedParameters* out_params,
 403     CryptoHandshakeMessage* out,
 404     string* error_details) const {
 405   DCHECK(error_details != nullptr);
 406
 407   FillInchoateClientHello(server_id, preferred_version, cached,
 408                           out_params, out);
 409
 410   const CryptoHandshakeMessage* scfg = cached->GetServerConfig();
 411   if (!scfg) {
 412     // This should never happen as our caller should have checked
 413     // cached->IsComplete() before calling this function.
 414     *error_details = "Handshake not ready";
 415     return QUIC_CRYPTO_INTERNAL_ERROR;
 416   }
 417
 418   StringPiece scid;
 419   if (!scfg->GetStringPiece(kSCID, &scid)) {
 420     *error_details = "SCFG missing SCID";
 421     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 422   }
 423   out->SetStringPiece(kSCID, scid);
 424
 425   const QuicTag* their_aeads;
 426   const QuicTag* their_key_exchanges;
 427   size_t num_their_aeads, num_their_key_exchanges;
 428   if (scfg->GetTaglist(kAEAD, &their_aeads,
 429                        &num_their_aeads) != QUIC_NO_ERROR ||
 430       scfg->GetTaglist(kKEXS, &their_key_exchanges,
 431                        &num_their_key_exchanges) != QUIC_NO_ERROR) {
 432     *error_details = "Missing AEAD or KEXS";
 433     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 434   }
 435
 436   // AEAD: the work loads on the client and server are symmetric. Since the
 437   // client is more likely to be CPU-constrained, break the tie by favoring
 438   // the client's preference.
 439   // Key exchange: the client does more work than the server, so favor the
 440   // client's preference.
 441   size_t key_exchange_index;
 442   if (!QuicUtils::FindMutualTag(
 443           aead, their_aeads, num_their_aeads, QuicUtils::LOCAL_PRIORITY,
 444           &out_params->aead, nullptr) ||
 445       !QuicUtils::FindMutualTag(
 446           kexs, their_key_exchanges, num_their_key_exchanges,
 447           QuicUtils::LOCAL_PRIORITY, &out_params->key_exchange,
 448           &key_exchange_index)) {
 449     *error_details = "Unsupported AEAD or KEXS";
 450     return QUIC_CRYPTO_NO_SUPPORT;
 451   }
 452   out->SetTaglist(kAEAD, out_params->aead, 0);
 453   out->SetTaglist(kKEXS, out_params->key_exchange, 0);
 454
 455   StringPiece public_value;
 456   if (scfg->GetNthValue24(kPUBS, key_exchange_index, &public_value) !=
 457           QUIC_NO_ERROR) {
 458     *error_details = "Missing public value";
 459     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 460   }
 461
 462   StringPiece orbit;
 463   if (!scfg->GetStringPiece(kORBT, &orbit) || orbit.size() != kOrbitSize) {
 464     *error_details = "SCFG missing OBIT";
 465     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 466   }
 467
 468   CryptoUtils::GenerateNonce(now, rand, orbit, &out_params->client_nonce);
 469   out->SetStringPiece(kNONC, out_params->client_nonce);
 470   if (!out_params->server_nonce.empty()) {
 471     out->SetStringPiece(kServerNonceTag, out_params->server_nonce);
 472   }
 473
 474   switch (out_params->key_exchange) {
 475     case kC255:
 476       out_params->client_key_exchange.reset(Curve25519KeyExchange::New(
 477           Curve25519KeyExchange::NewPrivateKey(rand)));
 478       break;
 479     case kP256:
 480       out_params->client_key_exchange.reset(P256KeyExchange::New(
 481           P256KeyExchange::NewPrivateKey()));
 482       break;
 483     default:
 484       DCHECK(false);
 485       *error_details = "Configured to support an unknown key exchange";
 486       return QUIC_CRYPTO_INTERNAL_ERROR;
 487   }
 488
 489   if (!out_params->client_key_exchange->CalculateSharedKey(
 490           public_value, &out_params->initial_premaster_secret)) {
 491     *error_details = "Key exchange failure";
 492     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 493   }
 494   out->SetStringPiece(kPUBS, out_params->client_key_exchange->public_value());
 495
 496   if (channel_id_key) {
 497     // In order to calculate the encryption key for the CETV block we need to
 498     // serialise the client hello as it currently is (i.e. without the CETV
 499     // block). For this, the client hello is serialized without padding.
 500     const size_t orig_min_size = out->minimum_size();
 501     out->set_minimum_size(0);
 502
 503     CryptoHandshakeMessage cetv;
 504     cetv.set_tag(kCETV);
 505
 506     string hkdf_input;
 507     const QuicData& client_hello_serialized = out->GetSerialized();
 508     hkdf_input.append(QuicCryptoConfig::kCETVLabel,
 509                       strlen(QuicCryptoConfig::kCETVLabel) + 1);
 510     hkdf_input.append(reinterpret_cast<char*>(&connection_id),
 511                       sizeof(connection_id));
 512     hkdf_input.append(client_hello_serialized.data(),
 513                       client_hello_serialized.length());
 514     hkdf_input.append(cached->server_config());
 515
 516     string key = channel_id_key->SerializeKey();
 517     string signature;
 518     if (!channel_id_key->Sign(hkdf_input, &signature)) {
 519       *error_details = "Channel ID signature failed";
 520       return QUIC_INVALID_CHANNEL_ID_SIGNATURE;
 521     }
 522
 523     cetv.SetStringPiece(kCIDK, key);
 524     cetv.SetStringPiece(kCIDS, signature);
 525
 526     CrypterPair crypters;
 527     if (!CryptoUtils::DeriveKeys(out_params->initial_premaster_secret,
 528                                  out_params->aead, out_params->client_nonce,
 529                                  out_params->server_nonce, hkdf_input,
 530                                  CryptoUtils::CLIENT, &crypters,
 531                                  nullptr /* subkey secret */)) {
 532       *error_details = "Symmetric key setup failed";
 533       return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 534     }
 535
 536     const QuicData& cetv_plaintext = cetv.GetSerialized();
 537     scoped_ptr<QuicData> cetv_ciphertext(crypters.encrypter->EncryptPacket(
 538         0 /* sequence number */,
 539         StringPiece() /* associated data */,
 540         cetv_plaintext.AsStringPiece()));
 541     if (!cetv_ciphertext.get()) {
 542       *error_details = "Packet encryption failed";
 543       return QUIC_ENCRYPTION_FAILURE;
 544     }
 545
 546     out->SetStringPiece(kCETV, cetv_ciphertext->AsStringPiece());
 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            CryptoUtils::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   COMPILE_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            CryptoUtils::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 = 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   QuicServerId suffix_server_id(canonical_suffixes_[i], server_id.port(),
 854                                 server_id.is_https(),
 855                                 server_id.privacy_mode());
 856   if (!ContainsKey(canonical_server_map_, suffix_server_id)) {
 857     // This is the first host we've seen which matches the suffix, so make it
 858     // canonical.
 859     canonical_server_map_[suffix_server_id] = server_id;
 860     return false;
 861   }
 862
 863   const QuicServerId& canonical_server_id =
 864       canonical_server_map_[suffix_server_id];
 865   CachedState* canonical_state = cached_states_[canonical_server_id];
 866   if (!canonical_state->proof_valid()) {
 867     return false;
 868   }
 869
 870   // Update canonical version to point at the "most recent" entry.
 871   canonical_server_map_[suffix_server_id] = server_id;
 872
 873   server_state->InitializeFrom(*canonical_state);
 874   return true;
 875 }
 876
 877 }  // namespace net