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/profiler/scoped_tracker.h"
  10 #include "base/stl_util.h"
  11 #include "base/strings/string_util.h"
  12 #include "net/quic/crypto/cert_compressor.h"
  13 #include "net/quic/crypto/chacha20_poly1305_encrypter.h"
  14 #include "net/quic/crypto/channel_id.h"
  15 #include "net/quic/crypto/common_cert_set.h"
  16 #include "net/quic/crypto/crypto_framer.h"
  17 #include "net/quic/crypto/crypto_utils.h"
  18 #include "net/quic/crypto/curve25519_key_exchange.h"
  19 #include "net/quic/crypto/key_exchange.h"
  20 #include "net/quic/crypto/p256_key_exchange.h"
  21 #include "net/quic/crypto/proof_verifier.h"
  22 #include "net/quic/crypto/quic_encrypter.h"
  23 #include "net/quic/quic_utils.h"
  24
  25 using base::StringPiece;
  26 using std::map;
  27 using std::string;
  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 QuicCryptoClientConfig::CachedState::ServerConfigState
 122 QuicCryptoClientConfig::CachedState::SetServerConfig(
 123     StringPiece server_config, QuicWallTime now, string* error_details) {
 124   const bool matches_existing = server_config == server_config_;
 125
 126   // Even if the new server config matches the existing one, we still wish to
 127   // reject it if it has expired.
 128   scoped_ptr<CryptoHandshakeMessage> new_scfg_storage;
 129   const CryptoHandshakeMessage* new_scfg;
 130
 131   if (!matches_existing) {
 132     new_scfg_storage.reset(CryptoFramer::ParseMessage(server_config));
 133     new_scfg = new_scfg_storage.get();
 134   } else {
 135     new_scfg = GetServerConfig();
 136   }
 137
 138   if (!new_scfg) {
 139     *error_details = "SCFG invalid";
 140     return SERVER_CONFIG_INVALID;
 141   }
 142
 143   uint64 expiry_seconds;
 144   if (new_scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
 145     *error_details = "SCFG missing EXPY";
 146     return SERVER_CONFIG_INVALID_EXPIRY;
 147   }
 148
 149   if (now.ToUNIXSeconds() >= expiry_seconds) {
 150     *error_details = "SCFG has expired";
 151     return SERVER_CONFIG_EXPIRED;
 152   }
 153
 154   if (!matches_existing) {
 155     server_config_ = server_config.as_string();
 156     SetProofInvalid();
 157     scfg_.reset(new_scfg_storage.release());
 158   }
 159   return SERVER_CONFIG_VALID;
 160 }
 161
 162 void QuicCryptoClientConfig::CachedState::InvalidateServerConfig() {
 163   server_config_.clear();
 164   scfg_.reset();
 165   SetProofInvalid();
 166 }
 167
 168 void QuicCryptoClientConfig::CachedState::SetProof(const vector<string>& certs,
 169                                                    StringPiece signature) {
 170   bool has_changed =
 171       signature != server_config_sig_ || certs_.size() != certs.size();
 172
 173   if (!has_changed) {
 174     for (size_t i = 0; i < certs_.size(); i++) {
 175       if (certs_[i] != certs[i]) {
 176         has_changed = true;
 177         break;
 178       }
 179     }
 180   }
 181
 182   if (!has_changed) {
 183     return;
 184   }
 185
 186   // If the proof has changed then it needs to be revalidated.
 187   SetProofInvalid();
 188   certs_ = certs;
 189   server_config_sig_ = signature.as_string();
 190 }
 191
 192 void QuicCryptoClientConfig::CachedState::Clear() {
 193   server_config_.clear();
 194   source_address_token_.clear();
 195   certs_.clear();
 196   server_config_sig_.clear();
 197   server_config_valid_ = false;
 198   proof_verify_details_.reset();
 199   scfg_.reset();
 200   ++generation_counter_;
 201 }
 202
 203 void QuicCryptoClientConfig::CachedState::ClearProof() {
 204   SetProofInvalid();
 205   certs_.clear();
 206   server_config_sig_.clear();
 207 }
 208
 209 void QuicCryptoClientConfig::CachedState::SetProofValid() {
 210   server_config_valid_ = true;
 211 }
 212
 213 void QuicCryptoClientConfig::CachedState::SetProofInvalid() {
 214   server_config_valid_ = false;
 215   ++generation_counter_;
 216 }
 217
 218 bool QuicCryptoClientConfig::CachedState::Initialize(
 219     StringPiece server_config,
 220     StringPiece source_address_token,
 221     const vector<string>& certs,
 222     StringPiece signature,
 223     QuicWallTime now) {
 224   DCHECK(server_config_.empty());
 225
 226   if (server_config.empty()) {
 227     RecordDiskCacheServerConfigState(SERVER_CONFIG_EMPTY);
 228     return false;
 229   }
 230
 231   string error_details;
 232   ServerConfigState state = SetServerConfig(server_config, now,
 233                                             &error_details);
 234   RecordDiskCacheServerConfigState(state);
 235   if (state != SERVER_CONFIG_VALID) {
 236     DVLOG(1) << "SetServerConfig failed with " << error_details;
 237     return false;
 238   }
 239
 240   signature.CopyToString(&server_config_sig_);
 241   source_address_token.CopyToString(&source_address_token_);
 242   certs_ = certs;
 243   return true;
 244 }
 245
 246 const string& QuicCryptoClientConfig::CachedState::server_config() const {
 247   return server_config_;
 248 }
 249
 250 const string&
 251 QuicCryptoClientConfig::CachedState::source_address_token() const {
 252   return source_address_token_;
 253 }
 254
 255 const vector<string>& QuicCryptoClientConfig::CachedState::certs() const {
 256   return certs_;
 257 }
 258
 259 const string& QuicCryptoClientConfig::CachedState::signature() const {
 260   return server_config_sig_;
 261 }
 262
 263 bool QuicCryptoClientConfig::CachedState::proof_valid() const {
 264   return server_config_valid_;
 265 }
 266
 267 uint64 QuicCryptoClientConfig::CachedState::generation_counter() const {
 268   return generation_counter_;
 269 }
 270
 271 const ProofVerifyDetails*
 272 QuicCryptoClientConfig::CachedState::proof_verify_details() const {
 273   return proof_verify_details_.get();
 274 }
 275
 276 void QuicCryptoClientConfig::CachedState::set_source_address_token(
 277     StringPiece token) {
 278   source_address_token_ = token.as_string();
 279 }
 280
 281 void QuicCryptoClientConfig::CachedState::SetProofVerifyDetails(
 282     ProofVerifyDetails* details) {
 283   proof_verify_details_.reset(details);
 284 }
 285
 286 void QuicCryptoClientConfig::CachedState::InitializeFrom(
 287     const QuicCryptoClientConfig::CachedState& other) {
 288   DCHECK(server_config_.empty());
 289   DCHECK(!server_config_valid_);
 290   server_config_ = other.server_config_;
 291   source_address_token_ = other.source_address_token_;
 292   certs_ = other.certs_;
 293   server_config_sig_ = other.server_config_sig_;
 294   server_config_valid_ = other.server_config_valid_;
 295   if (other.proof_verify_details_.get() != nullptr) {
 296     proof_verify_details_.reset(other.proof_verify_details_->Clone());
 297   }
 298   ++generation_counter_;
 299 }
 300
 301 void QuicCryptoClientConfig::SetDefaults() {
 302   // Key exchange methods.
 303   kexs.resize(2);
 304   kexs[0] = kC255;
 305   kexs[1] = kP256;
 306
 307   // Authenticated encryption algorithms. Prefer ChaCha20 by default.
 308   aead.clear();
 309   if (ChaCha20Poly1305Encrypter::IsSupported()) {
 310     aead.push_back(kCC12);
 311   }
 312   aead.push_back(kAESG);
 313
 314   disable_ecdsa_ = false;
 315 }
 316
 317 QuicCryptoClientConfig::CachedState* QuicCryptoClientConfig::LookupOrCreate(
 318     const QuicServerId& server_id) {
 319   CachedStateMap::const_iterator it = cached_states_.find(server_id);
 320   if (it != cached_states_.end()) {
 321     return it->second;
 322   }
 323
 324   CachedState* cached = new CachedState;
 325   cached_states_.insert(std::make_pair(server_id, cached));
 326   bool cache_populated = PopulateFromCanonicalConfig(server_id, cached);
 327   UMA_HISTOGRAM_BOOLEAN(
 328       "Net.QuicCryptoClientConfig.PopulatedFromCanonicalConfig",
 329       cache_populated);
 330   return cached;
 331 }
 332
 333 void QuicCryptoClientConfig::ClearCachedStates() {
 334   for (CachedStateMap::const_iterator it = cached_states_.begin();
 335        it != cached_states_.end(); ++it) {
 336     it->second->Clear();
 337   }
 338 }
 339
 340 void QuicCryptoClientConfig::FillInchoateClientHello(
 341     const QuicServerId& server_id,
 342     const QuicVersion preferred_version,
 343     const CachedState* cached,
 344     QuicCryptoNegotiatedParameters* out_params,
 345     CryptoHandshakeMessage* out) const {
 346   // TODO(vadimt): Remove ScopedTracker below once crbug.com/422516 is fixed.
 347   tracked_objects::ScopedTracker tracking_profile(
 348       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 349           "422516 QuicCryptoClientConfig::FillInchoateClientHello"));
 350
 351   out->set_tag(kCHLO);
 352   out->set_minimum_size(kClientHelloMinimumSize);
 353
 354   // Server name indication. We only send SNI if it's a valid domain name, as
 355   // per the spec.
 356   if (CryptoUtils::IsValidSNI(server_id.host())) {
 357     out->SetStringPiece(kSNI, server_id.host());
 358   }
 359   out->SetValue(kVER, QuicVersionToQuicTag(preferred_version));
 360
 361   if (!user_agent_id_.empty()) {
 362     out->SetStringPiece(kUAID, user_agent_id_);
 363   }
 364
 365   if (!cached->source_address_token().empty()) {
 366     out->SetStringPiece(kSourceAddressTokenTag, cached->source_address_token());
 367   }
 368
 369   if (server_id.is_https()) {
 370     if (disable_ecdsa_) {
 371       out->SetTaglist(kPDMD, kX59R, 0);
 372     } else {
 373       out->SetTaglist(kPDMD, kX509, 0);
 374     }
 375   }
 376
 377   if (common_cert_sets) {
 378     out->SetStringPiece(kCCS, common_cert_sets->GetCommonHashes());
 379   }
 380
 381   const vector<string>& certs = cached->certs();
 382   // We save |certs| in the QuicCryptoNegotiatedParameters so that, if the
 383   // client config is being used for multiple connections, another connection
 384   // doesn't update the cached certificates and cause us to be unable to
 385   // process the server's compressed certificate chain.
 386   out_params->cached_certs = certs;
 387   if (!certs.empty()) {
 388     vector<uint64> hashes;
 389     hashes.reserve(certs.size());
 390     for (vector<string>::const_iterator i = certs.begin();
 391          i != certs.end(); ++i) {
 392       hashes.push_back(QuicUtils::FNV1a_64_Hash(i->data(), i->size()));
 393     }
 394     out->SetVector(kCCRT, hashes);
 395   }
 396 }
 397
 398 QuicErrorCode QuicCryptoClientConfig::FillClientHello(
 399     const QuicServerId& server_id,
 400     QuicConnectionId connection_id,
 401     const QuicVersion preferred_version,
 402     const CachedState* cached,
 403     QuicWallTime now,
 404     QuicRandom* rand,
 405     const ChannelIDKey* channel_id_key,
 406     QuicCryptoNegotiatedParameters* out_params,
 407     CryptoHandshakeMessage* out,
 408     string* error_details) const {
 409   // TODO(vadimt): Remove ScopedTracker below once crbug.com/422516 is fixed.
 410   tracked_objects::ScopedTracker tracking_profile(
 411       FROM_HERE_WITH_EXPLICIT_FUNCTION(
 412           "422516 QuicCryptoClientConfig::FillClientHello"));
 413
 414   DCHECK(error_details != nullptr);
 415
 416   FillInchoateClientHello(server_id, preferred_version, cached,
 417                           out_params, out);
 418
 419   const CryptoHandshakeMessage* scfg = cached->GetServerConfig();
 420   if (!scfg) {
 421     // This should never happen as our caller should have checked
 422     // cached->IsComplete() before calling this function.
 423     *error_details = "Handshake not ready";
 424     return QUIC_CRYPTO_INTERNAL_ERROR;
 425   }
 426
 427   StringPiece scid;
 428   if (!scfg->GetStringPiece(kSCID, &scid)) {
 429     *error_details = "SCFG missing SCID";
 430     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 431   }
 432   out->SetStringPiece(kSCID, scid);
 433
 434   const QuicTag* their_aeads;
 435   const QuicTag* their_key_exchanges;
 436   size_t num_their_aeads, num_their_key_exchanges;
 437   if (scfg->GetTaglist(kAEAD, &their_aeads,
 438                        &num_their_aeads) != QUIC_NO_ERROR ||
 439       scfg->GetTaglist(kKEXS, &their_key_exchanges,
 440                        &num_their_key_exchanges) != QUIC_NO_ERROR) {
 441     *error_details = "Missing AEAD or KEXS";
 442     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 443   }
 444
 445   // AEAD: the work loads on the client and server are symmetric. Since the
 446   // client is more likely to be CPU-constrained, break the tie by favoring
 447   // the client's preference.
 448   // Key exchange: the client does more work than the server, so favor the
 449   // client's preference.
 450   size_t key_exchange_index;
 451   if (!QuicUtils::FindMutualTag(
 452           aead, their_aeads, num_their_aeads, QuicUtils::LOCAL_PRIORITY,
 453           &out_params->aead, nullptr) ||
 454       !QuicUtils::FindMutualTag(
 455           kexs, their_key_exchanges, num_their_key_exchanges,
 456           QuicUtils::LOCAL_PRIORITY, &out_params->key_exchange,
 457           &key_exchange_index)) {
 458     *error_details = "Unsupported AEAD or KEXS";
 459     return QUIC_CRYPTO_NO_SUPPORT;
 460   }
 461   out->SetTaglist(kAEAD, out_params->aead, 0);
 462   out->SetTaglist(kKEXS, out_params->key_exchange, 0);
 463
 464   StringPiece public_value;
 465   if (scfg->GetNthValue24(kPUBS, key_exchange_index, &public_value) !=
 466           QUIC_NO_ERROR) {
 467     *error_details = "Missing public value";
 468     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 469   }
 470
 471   StringPiece orbit;
 472   if (!scfg->GetStringPiece(kORBT, &orbit) || orbit.size() != kOrbitSize) {
 473     *error_details = "SCFG missing OBIT";
 474     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 475   }
 476
 477   CryptoUtils::GenerateNonce(now, rand, orbit, &out_params->client_nonce);
 478   out->SetStringPiece(kNONC, out_params->client_nonce);
 479   if (!out_params->server_nonce.empty()) {
 480     out->SetStringPiece(kServerNonceTag, out_params->server_nonce);
 481   }
 482
 483   switch (out_params->key_exchange) {
 484     case kC255:
 485       out_params->client_key_exchange.reset(Curve25519KeyExchange::New(
 486           Curve25519KeyExchange::NewPrivateKey(rand)));
 487       break;
 488     case kP256:
 489       out_params->client_key_exchange.reset(P256KeyExchange::New(
 490           P256KeyExchange::NewPrivateKey()));
 491       break;
 492     default:
 493       DCHECK(false);
 494       *error_details = "Configured to support an unknown key exchange";
 495       return QUIC_CRYPTO_INTERNAL_ERROR;
 496   }
 497
 498   if (!out_params->client_key_exchange->CalculateSharedKey(
 499           public_value, &out_params->initial_premaster_secret)) {
 500     *error_details = "Key exchange failure";
 501     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 502   }
 503   out->SetStringPiece(kPUBS, out_params->client_key_exchange->public_value());
 504
 505   if (channel_id_key) {
 506     // In order to calculate the encryption key for the CETV block we need to
 507     // serialise the client hello as it currently is (i.e. without the CETV
 508     // block). For this, the client hello is serialized without padding.
 509     const size_t orig_min_size = out->minimum_size();
 510     out->set_minimum_size(0);
 511
 512     CryptoHandshakeMessage cetv;
 513     cetv.set_tag(kCETV);
 514
 515     string hkdf_input;
 516     const QuicData& client_hello_serialized = out->GetSerialized();
 517     hkdf_input.append(QuicCryptoConfig::kCETVLabel,
 518                       strlen(QuicCryptoConfig::kCETVLabel) + 1);
 519     hkdf_input.append(reinterpret_cast<char*>(&connection_id),
 520                       sizeof(connection_id));
 521     hkdf_input.append(client_hello_serialized.data(),
 522                       client_hello_serialized.length());
 523     hkdf_input.append(cached->server_config());
 524
 525     string key = channel_id_key->SerializeKey();
 526     string signature;
 527     if (!channel_id_key->Sign(hkdf_input, &signature)) {
 528       *error_details = "Channel ID signature failed";
 529       return QUIC_INVALID_CHANNEL_ID_SIGNATURE;
 530     }
 531
 532     cetv.SetStringPiece(kCIDK, key);
 533     cetv.SetStringPiece(kCIDS, signature);
 534
 535     CrypterPair crypters;
 536     if (!CryptoUtils::DeriveKeys(out_params->initial_premaster_secret,
 537                                  out_params->aead, out_params->client_nonce,
 538                                  out_params->server_nonce, hkdf_input,
 539                                  CryptoUtils::CLIENT, &crypters,
 540                                  nullptr /* subkey secret */)) {
 541       *error_details = "Symmetric key setup failed";
 542       return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 543     }
 544
 545     const QuicData& cetv_plaintext = cetv.GetSerialized();
 546     const size_t encrypted_len =
 547         crypters.encrypter->GetCiphertextSize(cetv_plaintext.length());
 548     scoped_ptr<char[]> output(new char[encrypted_len]);
 549     size_t output_size = 0;
 550     if (!crypters.encrypter->EncryptPacket(
 551             0 /* sequence number */, StringPiece() /* associated data */,
 552             cetv_plaintext.AsStringPiece(), output.get(), &output_size,
 553             encrypted_len)) {
 554       *error_details = "Packet encryption failed";
 555       return QUIC_ENCRYPTION_FAILURE;
 556     }
 557
 558     out->SetStringPiece(kCETV, StringPiece(output.get(), output_size));
 559     out->MarkDirty();
 560
 561     out->set_minimum_size(orig_min_size);
 562   }
 563
 564   // Derive the symmetric keys and set up the encrypters and decrypters.
 565   // Set the following members of out_params:
 566   //   out_params->hkdf_input_suffix
 567   //   out_params->initial_crypters
 568   out_params->hkdf_input_suffix.clear();
 569   out_params->hkdf_input_suffix.append(reinterpret_cast<char*>(&connection_id),
 570                                        sizeof(connection_id));
 571   const QuicData& client_hello_serialized = out->GetSerialized();
 572   out_params->hkdf_input_suffix.append(client_hello_serialized.data(),
 573                                        client_hello_serialized.length());
 574   out_params->hkdf_input_suffix.append(cached->server_config());
 575
 576   string hkdf_input;
 577   const size_t label_len = strlen(QuicCryptoConfig::kInitialLabel) + 1;
 578   hkdf_input.reserve(label_len + out_params->hkdf_input_suffix.size());
 579   hkdf_input.append(QuicCryptoConfig::kInitialLabel, label_len);
 580   hkdf_input.append(out_params->hkdf_input_suffix);
 581
 582   if (!CryptoUtils::DeriveKeys(
 583            out_params->initial_premaster_secret, out_params->aead,
 584            out_params->client_nonce, out_params->server_nonce, hkdf_input,
 585            CryptoUtils::CLIENT, &out_params->initial_crypters,
 586            nullptr /* subkey secret */)) {
 587     *error_details = "Symmetric key setup failed";
 588     return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 589   }
 590
 591   return QUIC_NO_ERROR;
 592 }
 593
 594 QuicErrorCode QuicCryptoClientConfig::CacheNewServerConfig(
 595     const CryptoHandshakeMessage& message,
 596     QuicWallTime now,
 597     const vector<string>& cached_certs,
 598     CachedState* cached,
 599     string* error_details) {
 600   DCHECK(error_details != nullptr);
 601
 602   StringPiece scfg;
 603   if (!message.GetStringPiece(kSCFG, &scfg)) {
 604     *error_details = "Missing SCFG";
 605     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 606   }
 607
 608   CachedState::ServerConfigState state = cached->SetServerConfig(
 609       scfg, now, error_details);
 610   if (state == CachedState::SERVER_CONFIG_EXPIRED) {
 611     return QUIC_CRYPTO_SERVER_CONFIG_EXPIRED;
 612   }
 613   // TODO(rtenneti): Return more specific error code than returning
 614   // QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER.
 615   if (state != CachedState::SERVER_CONFIG_VALID) {
 616     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 617   }
 618
 619   StringPiece token;
 620   if (message.GetStringPiece(kSourceAddressTokenTag, &token)) {
 621     cached->set_source_address_token(token);
 622   }
 623
 624   StringPiece proof, cert_bytes;
 625   bool has_proof = message.GetStringPiece(kPROF, &proof);
 626   bool has_cert = message.GetStringPiece(kCertificateTag, &cert_bytes);
 627   if (has_proof && has_cert) {
 628     vector<string> certs;
 629     if (!CertCompressor::DecompressChain(cert_bytes, cached_certs,
 630                                          common_cert_sets, &certs)) {
 631       *error_details = "Certificate data invalid";
 632       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 633     }
 634
 635     cached->SetProof(certs, proof);
 636   } else {
 637     if (proof_verifier() != nullptr) {
 638       // Secure QUIC: clear existing proof as we have been sent a new SCFG
 639       // without matching proof/certs.
 640       cached->ClearProof();
 641     }
 642
 643     if (has_proof && !has_cert) {
 644       *error_details = "Certificate missing";
 645       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 646     }
 647
 648     if (!has_proof && has_cert) {
 649       *error_details = "Proof missing";
 650       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 651     }
 652   }
 653
 654   return QUIC_NO_ERROR;
 655 }
 656
 657 QuicErrorCode QuicCryptoClientConfig::ProcessRejection(
 658     const CryptoHandshakeMessage& rej,
 659     QuicWallTime now,
 660     CachedState* cached,
 661     bool is_https,
 662     QuicCryptoNegotiatedParameters* out_params,
 663     string* error_details) {
 664   DCHECK(error_details != nullptr);
 665
 666   if (rej.tag() != kREJ) {
 667     *error_details = "Message is not REJ";
 668     return QUIC_CRYPTO_INTERNAL_ERROR;
 669   }
 670
 671   QuicErrorCode error = CacheNewServerConfig(rej, now, out_params->cached_certs,
 672                                              cached, error_details);
 673   if (error != QUIC_NO_ERROR) {
 674     return error;
 675   }
 676
 677   StringPiece nonce;
 678   if (rej.GetStringPiece(kServerNonceTag, &nonce)) {
 679     out_params->server_nonce = nonce.as_string();
 680   }
 681
 682   const uint32* reject_reasons;
 683   size_t num_reject_reasons;
 684   static_assert(sizeof(QuicTag) == sizeof(uint32), "header out of sync");
 685   if (rej.GetTaglist(kRREJ, &reject_reasons,
 686                      &num_reject_reasons) == QUIC_NO_ERROR) {
 687     uint32 packed_error = 0;
 688     for (size_t i = 0; i < num_reject_reasons; ++i) {
 689       // HANDSHAKE_OK is 0 and don't report that as error.
 690       if (reject_reasons[i] == HANDSHAKE_OK || reject_reasons[i] >= 32) {
 691         continue;
 692       }
 693       HandshakeFailureReason reason =
 694           static_cast<HandshakeFailureReason>(reject_reasons[i]);
 695       packed_error |= 1 << (reason - 1);
 696     }
 697     DVLOG(1) << "Reasons for rejection: " << packed_error;
 698     if (is_https) {
 699       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons.Secure",
 700                                   packed_error);
 701     } else {
 702       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons.Insecure",
 703                                   packed_error);
 704     }
 705   }
 706
 707   return QUIC_NO_ERROR;
 708 }
 709
 710 QuicErrorCode QuicCryptoClientConfig::ProcessServerHello(
 711     const CryptoHandshakeMessage& server_hello,
 712     QuicConnectionId connection_id,
 713     const QuicVersionVector& negotiated_versions,
 714     CachedState* cached,
 715     QuicCryptoNegotiatedParameters* out_params,
 716     string* error_details) {
 717   DCHECK(error_details != nullptr);
 718
 719   if (server_hello.tag() != kSHLO) {
 720     *error_details = "Bad tag";
 721     return QUIC_INVALID_CRYPTO_MESSAGE_TYPE;
 722   }
 723
 724   const QuicTag* supported_version_tags;
 725   size_t num_supported_versions;
 726
 727   if (server_hello.GetTaglist(kVER, &supported_version_tags,
 728                               &num_supported_versions) != QUIC_NO_ERROR) {
 729     *error_details = "server hello missing version list";
 730     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 731   }
 732   if (!negotiated_versions.empty()) {
 733     bool mismatch = num_supported_versions != negotiated_versions.size();
 734     for (size_t i = 0; i < num_supported_versions && !mismatch; ++i) {
 735       mismatch = QuicTagToQuicVersion(supported_version_tags[i]) !=
 736           negotiated_versions[i];
 737     }
 738     // The server sent a list of supported versions, and the connection
 739     // reports that there was a version negotiation during the handshake.
 740       // Ensure that these two lists are identical.
 741     if (mismatch) {
 742       *error_details = "Downgrade attack detected";
 743       return QUIC_VERSION_NEGOTIATION_MISMATCH;
 744     }
 745   }
 746
 747   // Learn about updated source address tokens.
 748   StringPiece token;
 749   if (server_hello.GetStringPiece(kSourceAddressTokenTag, &token)) {
 750     cached->set_source_address_token(token);
 751   }
 752
 753   // TODO(agl):
 754   //   learn about updated SCFGs.
 755
 756   StringPiece public_value;
 757   if (!server_hello.GetStringPiece(kPUBS, &public_value)) {
 758     *error_details = "server hello missing forward secure public value";
 759     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 760   }
 761
 762   if (!out_params->client_key_exchange->CalculateSharedKey(
 763           public_value, &out_params->forward_secure_premaster_secret)) {
 764     *error_details = "Key exchange failure";
 765     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 766   }
 767
 768   string hkdf_input;
 769   const size_t label_len = strlen(QuicCryptoConfig::kForwardSecureLabel) + 1;
 770   hkdf_input.reserve(label_len + out_params->hkdf_input_suffix.size());
 771   hkdf_input.append(QuicCryptoConfig::kForwardSecureLabel, label_len);
 772   hkdf_input.append(out_params->hkdf_input_suffix);
 773
 774   if (!CryptoUtils::DeriveKeys(
 775            out_params->forward_secure_premaster_secret, out_params->aead,
 776            out_params->client_nonce, out_params->server_nonce, hkdf_input,
 777            CryptoUtils::CLIENT, &out_params->forward_secure_crypters,
 778            &out_params->subkey_secret)) {
 779     *error_details = "Symmetric key setup failed";
 780     return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 781   }
 782
 783   return QUIC_NO_ERROR;
 784 }
 785
 786 QuicErrorCode QuicCryptoClientConfig::ProcessServerConfigUpdate(
 787     const CryptoHandshakeMessage& server_config_update,
 788     QuicWallTime now,
 789     CachedState* cached,
 790     QuicCryptoNegotiatedParameters* out_params,
 791     string* error_details) {
 792   DCHECK(error_details != nullptr);
 793
 794   if (server_config_update.tag() != kSCUP) {
 795     *error_details = "ServerConfigUpdate must have kSCUP tag.";
 796     return QUIC_INVALID_CRYPTO_MESSAGE_TYPE;
 797   }
 798
 799   return CacheNewServerConfig(server_config_update, now,
 800                               out_params->cached_certs, cached, error_details);
 801 }
 802
 803 ProofVerifier* QuicCryptoClientConfig::proof_verifier() const {
 804   return proof_verifier_.get();
 805 }
 806
 807 void QuicCryptoClientConfig::SetProofVerifier(ProofVerifier* verifier) {
 808   proof_verifier_.reset(verifier);
 809 }
 810
 811 ChannelIDSource* QuicCryptoClientConfig::channel_id_source() const {
 812   return channel_id_source_.get();
 813 }
 814
 815 void QuicCryptoClientConfig::SetChannelIDSource(ChannelIDSource* source) {
 816   channel_id_source_.reset(source);
 817 }
 818
 819 void QuicCryptoClientConfig::InitializeFrom(
 820     const QuicServerId& server_id,
 821     const QuicServerId& canonical_server_id,
 822     QuicCryptoClientConfig* canonical_crypto_config) {
 823   CachedState* canonical_cached =
 824       canonical_crypto_config->LookupOrCreate(canonical_server_id);
 825   if (!canonical_cached->proof_valid()) {
 826     return;
 827   }
 828   CachedState* cached = LookupOrCreate(server_id);
 829   cached->InitializeFrom(*canonical_cached);
 830 }
 831
 832 void QuicCryptoClientConfig::AddCanonicalSuffix(const string& suffix) {
 833   canonical_suffixes_.push_back(suffix);
 834 }
 835
 836 void QuicCryptoClientConfig::PreferAesGcm() {
 837   DCHECK(!aead.empty());
 838   if (aead.size() <= 1) {
 839     return;
 840   }
 841   QuicTagVector::iterator pos = std::find(aead.begin(), aead.end(), kAESG);
 842   if (pos != aead.end()) {
 843     aead.erase(pos);
 844     aead.insert(aead.begin(), kAESG);
 845   }
 846 }
 847
 848 void QuicCryptoClientConfig::DisableEcdsa() {
 849   disable_ecdsa_ = true;
 850 }
 851
 852 bool QuicCryptoClientConfig::PopulateFromCanonicalConfig(
 853     const QuicServerId& server_id,
 854     CachedState* server_state) {
 855   DCHECK(server_state->IsEmpty());
 856   size_t i = 0;
 857   for (; i < canonical_suffixes_.size(); ++i) {
 858     if (EndsWith(server_id.host(), canonical_suffixes_[i], false)) {
 859       break;
 860     }
 861   }
 862   if (i == canonical_suffixes_.size()) {
 863     return false;
 864   }
 865
 866   QuicServerId suffix_server_id(canonical_suffixes_[i], server_id.port(),
 867                                 server_id.is_https(),
 868                                 server_id.privacy_mode());
 869   if (!ContainsKey(canonical_server_map_, suffix_server_id)) {
 870     // This is the first host we've seen which matches the suffix, so make it
 871     // canonical.
 872     canonical_server_map_[suffix_server_id] = server_id;
 873     return false;
 874   }
 875
 876   const QuicServerId& canonical_server_id =
 877       canonical_server_map_[suffix_server_id];
 878   CachedState* canonical_state = cached_states_[canonical_server_id];
 879   if (!canonical_state->proof_valid()) {
 880     return false;
 881   }
 882
 883   // Update canonical version to point at the "most recent" entry.
 884   canonical_server_map_[suffix_server_id] = server_id;
 885
 886   server_state->InitializeFrom(*canonical_state);
 887   return true;
 888 }
 889
 890 }  // namespace net