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