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 enum ServerConfigState {
  36   // WARNING: Do not change the numerical values of any of server config state.
  37   // Do not remove deprecated server config states - just comment them as
  38   // deprecated.
  39   SERVER_CONFIG_EMPTY = 0,
  40   SERVER_CONFIG_INVALID = 1,
  41   SERVER_CONFIG_CORRUPTED = 2,
  42   SERVER_CONFIG_EXPIRED = 3,
  43   SERVER_CONFIG_INVALID_EXPIRY = 4,
  44
  45   // NOTE: Add new server config states only immediately above this line. Make
  46   // sure to update the QuicServerConfigState enum in
  47   // tools/metrics/histograms/histograms.xml accordingly.
  48   SERVER_CONFIG_COUNT
  49 };
  50
  51 void RecordServerConfigState(ServerConfigState server_config_state) {
  52   UMA_HISTOGRAM_ENUMERATION("Net.QuicClientHelloServerConfigState",
  53                             server_config_state, SERVER_CONFIG_COUNT);
  54 }
  55
  56 }  // namespace
  57
  58 QuicCryptoClientConfig::QuicCryptoClientConfig()
  59     : disable_ecdsa_(false) {}
  60
  61 QuicCryptoClientConfig::~QuicCryptoClientConfig() {
  62   STLDeleteValues(&cached_states_);
  63 }
  64
  65 QuicCryptoClientConfig::CachedState::CachedState()
  66     : server_config_valid_(false),
  67       generation_counter_(0) {}
  68
  69 QuicCryptoClientConfig::CachedState::~CachedState() {}
  70
  71 bool QuicCryptoClientConfig::CachedState::IsComplete(QuicWallTime now) const {
  72   if (server_config_.empty()) {
  73     RecordServerConfigState(SERVER_CONFIG_EMPTY);
  74     return false;
  75   }
  76
  77   if (!server_config_valid_) {
  78     RecordServerConfigState(SERVER_CONFIG_INVALID);
  79     return false;
  80   }
  81
  82   const CryptoHandshakeMessage* scfg = GetServerConfig();
  83   if (!scfg) {
  84     // Should be impossible short of cache corruption.
  85     DCHECK(false);
  86     RecordServerConfigState(SERVER_CONFIG_CORRUPTED);
  87     return false;
  88   }
  89
  90   uint64 expiry_seconds;
  91   if (scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
  92     RecordServerConfigState(SERVER_CONFIG_INVALID_EXPIRY);
  93     return false;
  94   }
  95   if (now.ToUNIXSeconds() >= expiry_seconds) {
  96     UMA_HISTOGRAM_CUSTOM_TIMES(
  97         "Net.QuicClientHelloServerConfig.InvalidDuration",
  98         base::TimeDelta::FromSeconds(now.ToUNIXSeconds() - expiry_seconds),
  99         base::TimeDelta::FromMinutes(1), base::TimeDelta::FromDays(20), 50);
 100     RecordServerConfigState(SERVER_CONFIG_EXPIRED);
 101     return false;
 102   }
 103
 104   return true;
 105 }
 106
 107 bool QuicCryptoClientConfig::CachedState::IsEmpty() const {
 108   return server_config_.empty();
 109 }
 110
 111 const CryptoHandshakeMessage*
 112 QuicCryptoClientConfig::CachedState::GetServerConfig() const {
 113   if (server_config_.empty()) {
 114     return NULL;
 115   }
 116
 117   if (!scfg_.get()) {
 118     scfg_.reset(CryptoFramer::ParseMessage(server_config_));
 119     DCHECK(scfg_.get());
 120   }
 121   return scfg_.get();
 122 }
 123
 124 QuicErrorCode QuicCryptoClientConfig::CachedState::SetServerConfig(
 125     StringPiece server_config, QuicWallTime now, string* error_details) {
 126   const bool matches_existing = server_config == server_config_;
 127
 128   // Even if the new server config matches the existing one, we still wish to
 129   // reject it if it has expired.
 130   scoped_ptr<CryptoHandshakeMessage> new_scfg_storage;
 131   const CryptoHandshakeMessage* new_scfg;
 132
 133   if (!matches_existing) {
 134     new_scfg_storage.reset(CryptoFramer::ParseMessage(server_config));
 135     new_scfg = new_scfg_storage.get();
 136   } else {
 137     new_scfg = GetServerConfig();
 138   }
 139
 140   if (!new_scfg) {
 141     *error_details = "SCFG invalid";
 142     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 143   }
 144
 145   uint64 expiry_seconds;
 146   if (new_scfg->GetUint64(kEXPY, &expiry_seconds) != QUIC_NO_ERROR) {
 147     *error_details = "SCFG missing EXPY";
 148     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 149   }
 150
 151   if (now.ToUNIXSeconds() >= expiry_seconds) {
 152     *error_details = "SCFG has expired";
 153     return QUIC_CRYPTO_SERVER_CONFIG_EXPIRED;
 154   }
 155
 156   if (!matches_existing) {
 157     server_config_ = server_config.as_string();
 158     SetProofInvalid();
 159     scfg_.reset(new_scfg_storage.release());
 160   }
 161   return QUIC_NO_ERROR;
 162 }
 163
 164 void QuicCryptoClientConfig::CachedState::InvalidateServerConfig() {
 165   server_config_.clear();
 166   scfg_.reset();
 167   SetProofInvalid();
 168 }
 169
 170 void QuicCryptoClientConfig::CachedState::SetProof(const vector<string>& certs,
 171                                                    StringPiece signature) {
 172   bool has_changed =
 173       signature != server_config_sig_ || certs_.size() != certs.size();
 174
 175   if (!has_changed) {
 176     for (size_t i = 0; i < certs_.size(); i++) {
 177       if (certs_[i] != certs[i]) {
 178         has_changed = true;
 179         break;
 180       }
 181     }
 182   }
 183
 184   if (!has_changed) {
 185     return;
 186   }
 187
 188   // If the proof has changed then it needs to be revalidated.
 189   SetProofInvalid();
 190   certs_ = certs;
 191   server_config_sig_ = signature.as_string();
 192 }
 193
 194 void QuicCryptoClientConfig::CachedState::Clear() {
 195   server_config_.clear();
 196   source_address_token_.clear();
 197   certs_.clear();
 198   server_config_sig_.clear();
 199   server_config_valid_ = false;
 200   proof_verify_details_.reset();
 201   scfg_.reset();
 202   ++generation_counter_;
 203 }
 204
 205 void QuicCryptoClientConfig::CachedState::ClearProof() {
 206   SetProofInvalid();
 207   certs_.clear();
 208   server_config_sig_.clear();
 209 }
 210
 211 void QuicCryptoClientConfig::CachedState::SetProofValid() {
 212   server_config_valid_ = true;
 213 }
 214
 215 void QuicCryptoClientConfig::CachedState::SetProofInvalid() {
 216   server_config_valid_ = false;
 217   ++generation_counter_;
 218 }
 219
 220 bool QuicCryptoClientConfig::CachedState::Initialize(
 221     StringPiece server_config,
 222     StringPiece source_address_token,
 223     const vector<string>& certs,
 224     StringPiece signature,
 225     QuicWallTime now) {
 226   DCHECK(server_config_.empty());
 227
 228   if (server_config.empty()) {
 229     return false;
 230   }
 231
 232   string error_details;
 233   QuicErrorCode error = SetServerConfig(server_config, now,
 234                                         &error_details);
 235   if (error != QUIC_NO_ERROR) {
 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() != NULL) {
 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(make_pair(server_id, cached));
 326   PopulateFromCanonicalConfig(server_id, cached);
 327   return cached;
 328 }
 329
 330 void QuicCryptoClientConfig::ClearCachedStates() {
 331   for (CachedStateMap::const_iterator it = cached_states_.begin();
 332        it != cached_states_.end(); ++it) {
 333     it->second->Clear();
 334   }
 335 }
 336
 337 void QuicCryptoClientConfig::FillInchoateClientHello(
 338     const QuicServerId& server_id,
 339     const QuicVersion preferred_version,
 340     const CachedState* cached,
 341     QuicCryptoNegotiatedParameters* out_params,
 342     CryptoHandshakeMessage* out) const {
 343   out->set_tag(kCHLO);
 344   out->set_minimum_size(kClientHelloMinimumSize);
 345
 346   // Server name indication. We only send SNI if it's a valid domain name, as
 347   // per the spec.
 348   if (CryptoUtils::IsValidSNI(server_id.host())) {
 349     out->SetStringPiece(kSNI, server_id.host());
 350   }
 351   out->SetValue(kVER, QuicVersionToQuicTag(preferred_version));
 352
 353   if (!user_agent_id_.empty()) {
 354     out->SetStringPiece(kUAID, user_agent_id_);
 355   }
 356
 357   if (!cached->source_address_token().empty()) {
 358     out->SetStringPiece(kSourceAddressTokenTag, cached->source_address_token());
 359   }
 360
 361   if (server_id.is_https()) {
 362     if (disable_ecdsa_) {
 363       out->SetTaglist(kPDMD, kX59R, 0);
 364     } else {
 365       out->SetTaglist(kPDMD, kX509, 0);
 366     }
 367   }
 368
 369   if (common_cert_sets) {
 370     out->SetStringPiece(kCCS, common_cert_sets->GetCommonHashes());
 371   }
 372
 373   const vector<string>& certs = cached->certs();
 374   // We save |certs| in the QuicCryptoNegotiatedParameters so that, if the
 375   // client config is being used for multiple connections, another connection
 376   // doesn't update the cached certificates and cause us to be unable to
 377   // process the server's compressed certificate chain.
 378   out_params->cached_certs = certs;
 379   if (!certs.empty()) {
 380     vector<uint64> hashes;
 381     hashes.reserve(certs.size());
 382     for (vector<string>::const_iterator i = certs.begin();
 383          i != certs.end(); ++i) {
 384       hashes.push_back(QuicUtils::FNV1a_64_Hash(i->data(), i->size()));
 385     }
 386     out->SetVector(kCCRT, hashes);
 387   }
 388 }
 389
 390 QuicErrorCode QuicCryptoClientConfig::FillClientHello(
 391     const QuicServerId& server_id,
 392     QuicConnectionId connection_id,
 393     const QuicVersion preferred_version,
 394     const CachedState* cached,
 395     QuicWallTime now,
 396     QuicRandom* rand,
 397     const ChannelIDKey* channel_id_key,
 398     QuicCryptoNegotiatedParameters* out_params,
 399     CryptoHandshakeMessage* out,
 400     string* error_details) const {
 401   DCHECK(error_details != NULL);
 402
 403   FillInchoateClientHello(server_id, preferred_version, cached,
 404                           out_params, out);
 405
 406   const CryptoHandshakeMessage* scfg = cached->GetServerConfig();
 407   if (!scfg) {
 408     // This should never happen as our caller should have checked
 409     // cached->IsComplete() before calling this function.
 410     *error_details = "Handshake not ready";
 411     return QUIC_CRYPTO_INTERNAL_ERROR;
 412   }
 413
 414   StringPiece scid;
 415   if (!scfg->GetStringPiece(kSCID, &scid)) {
 416     *error_details = "SCFG missing SCID";
 417     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 418   }
 419   out->SetStringPiece(kSCID, scid);
 420
 421   const QuicTag* their_aeads;
 422   const QuicTag* their_key_exchanges;
 423   size_t num_their_aeads, num_their_key_exchanges;
 424   if (scfg->GetTaglist(kAEAD, &their_aeads,
 425                        &num_their_aeads) != QUIC_NO_ERROR ||
 426       scfg->GetTaglist(kKEXS, &their_key_exchanges,
 427                        &num_their_key_exchanges) != QUIC_NO_ERROR) {
 428     *error_details = "Missing AEAD or KEXS";
 429     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 430   }
 431
 432   // AEAD: the work loads on the client and server are symmetric. Since the
 433   // client is more likely to be CPU-constrained, break the tie by favoring
 434   // the client's preference.
 435   // Key exchange: the client does more work than the server, so favor the
 436   // client's preference.
 437   size_t key_exchange_index;
 438   if (!QuicUtils::FindMutualTag(
 439           aead, their_aeads, num_their_aeads, QuicUtils::LOCAL_PRIORITY,
 440           &out_params->aead, NULL) ||
 441       !QuicUtils::FindMutualTag(
 442           kexs, their_key_exchanges, num_their_key_exchanges,
 443           QuicUtils::LOCAL_PRIORITY, &out_params->key_exchange,
 444           &key_exchange_index)) {
 445     *error_details = "Unsupported AEAD or KEXS";
 446     return QUIC_CRYPTO_NO_SUPPORT;
 447   }
 448   out->SetTaglist(kAEAD, out_params->aead, 0);
 449   out->SetTaglist(kKEXS, out_params->key_exchange, 0);
 450
 451   StringPiece public_value;
 452   if (scfg->GetNthValue24(kPUBS, key_exchange_index, &public_value) !=
 453           QUIC_NO_ERROR) {
 454     *error_details = "Missing public value";
 455     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 456   }
 457
 458   StringPiece orbit;
 459   if (!scfg->GetStringPiece(kORBT, &orbit) || orbit.size() != kOrbitSize) {
 460     *error_details = "SCFG missing OBIT";
 461     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 462   }
 463
 464   CryptoUtils::GenerateNonce(now, rand, orbit, &out_params->client_nonce);
 465   out->SetStringPiece(kNONC, out_params->client_nonce);
 466   if (!out_params->server_nonce.empty()) {
 467     out->SetStringPiece(kServerNonceTag, out_params->server_nonce);
 468   }
 469
 470   switch (out_params->key_exchange) {
 471     case kC255:
 472       out_params->client_key_exchange.reset(Curve25519KeyExchange::New(
 473           Curve25519KeyExchange::NewPrivateKey(rand)));
 474       break;
 475     case kP256:
 476       out_params->client_key_exchange.reset(P256KeyExchange::New(
 477           P256KeyExchange::NewPrivateKey()));
 478       break;
 479     default:
 480       DCHECK(false);
 481       *error_details = "Configured to support an unknown key exchange";
 482       return QUIC_CRYPTO_INTERNAL_ERROR;
 483   }
 484
 485   if (!out_params->client_key_exchange->CalculateSharedKey(
 486           public_value, &out_params->initial_premaster_secret)) {
 487     *error_details = "Key exchange failure";
 488     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 489   }
 490   out->SetStringPiece(kPUBS, out_params->client_key_exchange->public_value());
 491
 492   if (channel_id_key) {
 493     // In order to calculate the encryption key for the CETV block we need to
 494     // serialise the client hello as it currently is (i.e. without the CETV
 495     // block). For this, the client hello is serialized without padding.
 496     const size_t orig_min_size = out->minimum_size();
 497     out->set_minimum_size(0);
 498
 499     CryptoHandshakeMessage cetv;
 500     cetv.set_tag(kCETV);
 501
 502     string hkdf_input;
 503     const QuicData& client_hello_serialized = out->GetSerialized();
 504     hkdf_input.append(QuicCryptoConfig::kCETVLabel,
 505                       strlen(QuicCryptoConfig::kCETVLabel) + 1);
 506     hkdf_input.append(reinterpret_cast<char*>(&connection_id),
 507                       sizeof(connection_id));
 508     hkdf_input.append(client_hello_serialized.data(),
 509                       client_hello_serialized.length());
 510     hkdf_input.append(cached->server_config());
 511
 512     string key = channel_id_key->SerializeKey();
 513     string signature;
 514     if (!channel_id_key->Sign(hkdf_input, &signature)) {
 515       *error_details = "Channel ID signature failed";
 516       return QUIC_INVALID_CHANNEL_ID_SIGNATURE;
 517     }
 518
 519     cetv.SetStringPiece(kCIDK, key);
 520     cetv.SetStringPiece(kCIDS, signature);
 521
 522     CrypterPair crypters;
 523     if (!CryptoUtils::DeriveKeys(out_params->initial_premaster_secret,
 524                                  out_params->aead, out_params->client_nonce,
 525                                  out_params->server_nonce, hkdf_input,
 526                                  CryptoUtils::CLIENT, &crypters,
 527                                  NULL /* subkey secret */)) {
 528       *error_details = "Symmetric key setup failed";
 529       return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 530     }
 531
 532     const QuicData& cetv_plaintext = cetv.GetSerialized();
 533     scoped_ptr<QuicData> cetv_ciphertext(crypters.encrypter->EncryptPacket(
 534         0 /* sequence number */,
 535         StringPiece() /* associated data */,
 536         cetv_plaintext.AsStringPiece()));
 537     if (!cetv_ciphertext.get()) {
 538       *error_details = "Packet encryption failed";
 539       return QUIC_ENCRYPTION_FAILURE;
 540     }
 541
 542     out->SetStringPiece(kCETV, cetv_ciphertext->AsStringPiece());
 543     out->MarkDirty();
 544
 545     out->set_minimum_size(orig_min_size);
 546   }
 547
 548   // Derive the symmetric keys and set up the encrypters and decrypters.
 549   // Set the following members of out_params:
 550   //   out_params->hkdf_input_suffix
 551   //   out_params->initial_crypters
 552   out_params->hkdf_input_suffix.clear();
 553   out_params->hkdf_input_suffix.append(reinterpret_cast<char*>(&connection_id),
 554                                        sizeof(connection_id));
 555   const QuicData& client_hello_serialized = out->GetSerialized();
 556   out_params->hkdf_input_suffix.append(client_hello_serialized.data(),
 557                                        client_hello_serialized.length());
 558   out_params->hkdf_input_suffix.append(cached->server_config());
 559
 560   string hkdf_input;
 561   const size_t label_len = strlen(QuicCryptoConfig::kInitialLabel) + 1;
 562   hkdf_input.reserve(label_len + out_params->hkdf_input_suffix.size());
 563   hkdf_input.append(QuicCryptoConfig::kInitialLabel, label_len);
 564   hkdf_input.append(out_params->hkdf_input_suffix);
 565
 566   if (!CryptoUtils::DeriveKeys(
 567            out_params->initial_premaster_secret, out_params->aead,
 568            out_params->client_nonce, out_params->server_nonce, hkdf_input,
 569            CryptoUtils::CLIENT, &out_params->initial_crypters,
 570            NULL /* subkey secret */)) {
 571     *error_details = "Symmetric key setup failed";
 572     return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 573   }
 574
 575   return QUIC_NO_ERROR;
 576 }
 577
 578 QuicErrorCode QuicCryptoClientConfig::CacheNewServerConfig(
 579     const CryptoHandshakeMessage& message,
 580     QuicWallTime now,
 581     const vector<string>& cached_certs,
 582     CachedState* cached,
 583     string* error_details) {
 584   DCHECK(error_details != NULL);
 585
 586   StringPiece scfg;
 587   if (!message.GetStringPiece(kSCFG, &scfg)) {
 588     *error_details = "Missing SCFG";
 589     return QUIC_CRYPTO_MESSAGE_PARAMETER_NOT_FOUND;
 590   }
 591
 592   QuicErrorCode error = cached->SetServerConfig(scfg, now, error_details);
 593   if (error != QUIC_NO_ERROR) {
 594     return error;
 595   }
 596
 597   StringPiece token;
 598   if (message.GetStringPiece(kSourceAddressTokenTag, &token)) {
 599     cached->set_source_address_token(token);
 600   }
 601
 602   StringPiece proof, cert_bytes;
 603   bool has_proof = message.GetStringPiece(kPROF, &proof);
 604   bool has_cert = message.GetStringPiece(kCertificateTag, &cert_bytes);
 605   if (has_proof && has_cert) {
 606     vector<string> certs;
 607     if (!CertCompressor::DecompressChain(cert_bytes, cached_certs,
 608                                          common_cert_sets, &certs)) {
 609       *error_details = "Certificate data invalid";
 610       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 611     }
 612
 613     cached->SetProof(certs, proof);
 614   } else {
 615     if (proof_verifier() != NULL) {
 616       // Secure QUIC: clear existing proof as we have been sent a new SCFG
 617       // without matching proof/certs.
 618       cached->ClearProof();
 619     }
 620
 621     if (has_proof && !has_cert) {
 622       *error_details = "Certificate missing";
 623       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 624     }
 625
 626     if (!has_proof && has_cert) {
 627       *error_details = "Proof missing";
 628       return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 629     }
 630   }
 631
 632   return QUIC_NO_ERROR;
 633 }
 634
 635 QuicErrorCode QuicCryptoClientConfig::ProcessRejection(
 636     const CryptoHandshakeMessage& rej,
 637     QuicWallTime now,
 638     CachedState* cached,
 639     bool is_https,
 640     QuicCryptoNegotiatedParameters* out_params,
 641     string* error_details) {
 642   DCHECK(error_details != NULL);
 643
 644   if (rej.tag() != kREJ) {
 645     *error_details = "Message is not REJ";
 646     return QUIC_CRYPTO_INTERNAL_ERROR;
 647   }
 648
 649   QuicErrorCode error = CacheNewServerConfig(rej, now, out_params->cached_certs,
 650                                              cached, error_details);
 651   if (error != QUIC_NO_ERROR) {
 652     return error;
 653   }
 654
 655   StringPiece nonce;
 656   if (rej.GetStringPiece(kServerNonceTag, &nonce)) {
 657     out_params->server_nonce = nonce.as_string();
 658   }
 659
 660   const uint32* reject_reasons;
 661   size_t num_reject_reasons;
 662   COMPILE_ASSERT(sizeof(QuicTag) == sizeof(uint32), header_out_of_sync);
 663   if (rej.GetTaglist(kRREJ, &reject_reasons,
 664                      &num_reject_reasons) == QUIC_NO_ERROR) {
 665     uint32 packed_error = 0;
 666     for (size_t i = 0; i < num_reject_reasons; ++i) {
 667       // HANDSHAKE_OK is 0 and don't report that as error.
 668       if (reject_reasons[i] == HANDSHAKE_OK || reject_reasons[i] >= 32) {
 669         continue;
 670       }
 671       HandshakeFailureReason reason =
 672           static_cast<HandshakeFailureReason>(reject_reasons[i]);
 673       packed_error |= 1 << (reason - 1);
 674     }
 675     DVLOG(1) << "Reasons for rejection: " << packed_error;
 676     if (is_https) {
 677       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons.Secure",
 678                                   packed_error);
 679     } else {
 680       UMA_HISTOGRAM_SPARSE_SLOWLY("Net.QuicClientHelloRejectReasons.Insecure",
 681                                   packed_error);
 682     }
 683   }
 684
 685   return QUIC_NO_ERROR;
 686 }
 687
 688 QuicErrorCode QuicCryptoClientConfig::ProcessServerHello(
 689     const CryptoHandshakeMessage& server_hello,
 690     QuicConnectionId connection_id,
 691     const QuicVersionVector& negotiated_versions,
 692     CachedState* cached,
 693     QuicCryptoNegotiatedParameters* out_params,
 694     string* error_details) {
 695   DCHECK(error_details != NULL);
 696
 697   if (server_hello.tag() != kSHLO) {
 698     *error_details = "Bad tag";
 699     return QUIC_INVALID_CRYPTO_MESSAGE_TYPE;
 700   }
 701
 702   const QuicTag* supported_version_tags;
 703   size_t num_supported_versions;
 704
 705   if (server_hello.GetTaglist(kVER, &supported_version_tags,
 706                               &num_supported_versions) != QUIC_NO_ERROR) {
 707     *error_details = "server hello missing version list";
 708     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 709   }
 710   if (!negotiated_versions.empty()) {
 711     bool mismatch = num_supported_versions != negotiated_versions.size();
 712     for (size_t i = 0; i < num_supported_versions && !mismatch; ++i) {
 713       mismatch = QuicTagToQuicVersion(supported_version_tags[i]) !=
 714           negotiated_versions[i];
 715     }
 716     // The server sent a list of supported versions, and the connection
 717     // reports that there was a version negotiation during the handshake.
 718       // Ensure that these two lists are identical.
 719     if (mismatch) {
 720       *error_details = "Downgrade attack detected";
 721       return QUIC_VERSION_NEGOTIATION_MISMATCH;
 722     }
 723   }
 724
 725   // Learn about updated source address tokens.
 726   StringPiece token;
 727   if (server_hello.GetStringPiece(kSourceAddressTokenTag, &token)) {
 728     cached->set_source_address_token(token);
 729   }
 730
 731   // TODO(agl):
 732   //   learn about updated SCFGs.
 733
 734   StringPiece public_value;
 735   if (!server_hello.GetStringPiece(kPUBS, &public_value)) {
 736     *error_details = "server hello missing forward secure public value";
 737     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 738   }
 739
 740   if (!out_params->client_key_exchange->CalculateSharedKey(
 741           public_value, &out_params->forward_secure_premaster_secret)) {
 742     *error_details = "Key exchange failure";
 743     return QUIC_INVALID_CRYPTO_MESSAGE_PARAMETER;
 744   }
 745
 746   string hkdf_input;
 747   const size_t label_len = strlen(QuicCryptoConfig::kForwardSecureLabel) + 1;
 748   hkdf_input.reserve(label_len + out_params->hkdf_input_suffix.size());
 749   hkdf_input.append(QuicCryptoConfig::kForwardSecureLabel, label_len);
 750   hkdf_input.append(out_params->hkdf_input_suffix);
 751
 752   if (!CryptoUtils::DeriveKeys(
 753            out_params->forward_secure_premaster_secret, out_params->aead,
 754            out_params->client_nonce, out_params->server_nonce, hkdf_input,
 755            CryptoUtils::CLIENT, &out_params->forward_secure_crypters,
 756            &out_params->subkey_secret)) {
 757     *error_details = "Symmetric key setup failed";
 758     return QUIC_CRYPTO_SYMMETRIC_KEY_SETUP_FAILED;
 759   }
 760
 761   return QUIC_NO_ERROR;
 762 }
 763
 764 QuicErrorCode QuicCryptoClientConfig::ProcessServerConfigUpdate(
 765     const CryptoHandshakeMessage& server_config_update,
 766     QuicWallTime now,
 767     CachedState* cached,
 768     QuicCryptoNegotiatedParameters* out_params,
 769     string* error_details) {
 770   DCHECK(error_details != NULL);
 771
 772   if (server_config_update.tag() != kSCUP) {
 773     *error_details = "ServerConfigUpdate must have kSCUP tag.";
 774     return QUIC_INVALID_CRYPTO_MESSAGE_TYPE;
 775   }
 776
 777   return CacheNewServerConfig(server_config_update, now,
 778                               out_params->cached_certs, cached, error_details);
 779 }
 780
 781 ProofVerifier* QuicCryptoClientConfig::proof_verifier() const {
 782   return proof_verifier_.get();
 783 }
 784
 785 void QuicCryptoClientConfig::SetProofVerifier(ProofVerifier* verifier) {
 786   proof_verifier_.reset(verifier);
 787 }
 788
 789 ChannelIDSource* QuicCryptoClientConfig::channel_id_source() const {
 790   return channel_id_source_.get();
 791 }
 792
 793 void QuicCryptoClientConfig::SetChannelIDSource(ChannelIDSource* source) {
 794   channel_id_source_.reset(source);
 795 }
 796
 797 void QuicCryptoClientConfig::InitializeFrom(
 798     const QuicServerId& server_id,
 799     const QuicServerId& canonical_server_id,
 800     QuicCryptoClientConfig* canonical_crypto_config) {
 801   CachedState* canonical_cached =
 802       canonical_crypto_config->LookupOrCreate(canonical_server_id);
 803   if (!canonical_cached->proof_valid()) {
 804     return;
 805   }
 806   CachedState* cached = LookupOrCreate(server_id);
 807   cached->InitializeFrom(*canonical_cached);
 808 }
 809
 810 void QuicCryptoClientConfig::AddCanonicalSuffix(const string& suffix) {
 811   canoncial_suffixes_.push_back(suffix);
 812 }
 813
 814 void QuicCryptoClientConfig::PreferAesGcm() {
 815   DCHECK(!aead.empty());
 816   if (aead.size() <= 1) {
 817     return;
 818   }
 819   QuicTagVector::iterator pos = find(aead.begin(), aead.end(), kAESG);
 820   if (pos != aead.end()) {
 821     aead.erase(pos);
 822     aead.insert(aead.begin(), kAESG);
 823   }
 824 }
 825
 826 void QuicCryptoClientConfig::DisableEcdsa() {
 827   disable_ecdsa_ = true;
 828 }
 829
 830 void QuicCryptoClientConfig::PopulateFromCanonicalConfig(
 831     const QuicServerId& server_id,
 832     CachedState* server_state) {
 833   DCHECK(server_state->IsEmpty());
 834   size_t i = 0;
 835   for (; i < canoncial_suffixes_.size(); ++i) {
 836     if (EndsWith(server_id.host(), canoncial_suffixes_[i], false)) {
 837       break;
 838     }
 839   }
 840   if (i == canoncial_suffixes_.size())
 841     return;
 842
 843   QuicServerId suffix_server_id(canoncial_suffixes_[i], server_id.port(),
 844                                 server_id.is_https(),
 845                                 server_id.privacy_mode());
 846   if (!ContainsKey(canonical_server_map_, suffix_server_id)) {
 847     // This is the first host we've seen which matches the suffix, so make it
 848     // canonical.
 849     canonical_server_map_[suffix_server_id] = server_id;
 850     return;
 851   }
 852
 853   const QuicServerId& canonical_server_id =
 854       canonical_server_map_[suffix_server_id];
 855   CachedState* canonical_state = cached_states_[canonical_server_id];
 856   if (!canonical_state->proof_valid()) {
 857     return;
 858   }
 859
 860   // Update canonical version to point at the "most recent" entry.
 861   canonical_server_map_[suffix_server_id] = server_id;
 862
 863   server_state->InitializeFrom(*canonical_state);
 864 }
 865
 866 }  // namespace net