Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2004-2023 Savoir-faire Linux Inc. |
| 3 | * |
Adrien Béraud | cb75362 | 2023-07-17 22:32:49 -0400 | [diff] [blame] | 4 | * This program is free software: you can redistribute it and/or modify |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 5 | * it under the terms of the GNU General Public License as published by |
Adrien Béraud | cb75362 | 2023-07-17 22:32:49 -0400 | [diff] [blame] | 6 | * the Free Software Foundation, either version 3 of the License, or |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
Adrien Béraud | cb75362 | 2023-07-17 22:32:49 -0400 | [diff] [blame] | 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 12 | * GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
Adrien Béraud | cb75362 | 2023-07-17 22:32:49 -0400 | [diff] [blame] | 15 | * along with this program. If not, see <https://www.gnu.org/licenses/>. |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 16 | */ |
| 17 | #include "tls_session.h" |
| 18 | #include "threadloop.h" |
| 19 | #include "certstore.h" |
| 20 | |
| 21 | #include <gnutls/gnutls.h> |
| 22 | #include <gnutls/dtls.h> |
| 23 | #include <gnutls/abstract.h> |
| 24 | |
| 25 | #include <gnutls/crypto.h> |
| 26 | #include <gnutls/ocsp.h> |
| 27 | #include <opendht/http.h> |
| 28 | #include <opendht/logger.h> |
| 29 | |
| 30 | #include <list> |
| 31 | #include <mutex> |
| 32 | #include <condition_variable> |
| 33 | #include <utility> |
| 34 | #include <map> |
| 35 | #include <atomic> |
| 36 | #include <iterator> |
| 37 | #include <stdexcept> |
| 38 | #include <algorithm> |
| 39 | #include <cstring> // std::memset |
| 40 | |
| 41 | #include <cstdlib> |
| 42 | #include <unistd.h> |
| 43 | |
Adrien Béraud | 1ae60aa | 2023-07-07 09:55:09 -0400 | [diff] [blame] | 44 | namespace dhtnet { |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 45 | namespace tls { |
| 46 | |
| 47 | static constexpr const char* DTLS_CERT_PRIORITY_STRING { |
| 48 | "SECURE192:-VERS-TLS-ALL:+VERS-DTLS-ALL:-RSA:%SERVER_PRECEDENCE:%SAFE_RENEGOTIATION"}; |
| 49 | static constexpr const char* DTLS_FULL_PRIORITY_STRING { |
| 50 | "SECURE192:-KX-ALL:+ANON-ECDH:+ANON-DH:+SECURE192:-VERS-TLS-ALL:+VERS-DTLS-ALL:-RSA:%SERVER_" |
| 51 | "PRECEDENCE:%SAFE_RENEGOTIATION"}; |
| 52 | // Note: -GROUP-FFDHE4096:-GROUP-FFDHE6144:-GROUP-FFDHE8192:+GROUP-X25519: |
| 53 | // is added after gnutls 3.6.7, because some safety checks were introduced for FFDHE resulting in a |
| 54 | // performance drop for our usage (2/3s of delay) This performance drop is visible on mobiles devices. |
| 55 | |
| 56 | // Benchmark result (on a computer) |
| 57 | // $gnutls-cli --benchmark-tls-kx |
| 58 | // (TLS1.3)-(DHE-FFDHE3072)-(RSA-PSS-RSAE-SHA256)-(AES-128-GCM) 20.48 transactions/sec |
| 59 | // (avg. handshake time: 48.45 ms, sample variance: 0.68) |
| 60 | // (TLS1.3)-(ECDHE-SECP256R1)-(RSA-PSS-RSAE-SHA256)-(AES-128-GCM) 208.14 transactions/sec |
| 61 | // (avg. handshake time: 4.01 ms, sample variance: 0.01) |
| 62 | // (TLS1.3)-(ECDHE-X25519)-(RSA-PSS-RSAE-SHA256)-(AES-128-GCM) 240.93 transactions/sec |
| 63 | // (avg. handshake time: 4.00 ms, sample variance: 0.00) |
| 64 | static constexpr const char* TLS_CERT_PRIORITY_STRING { |
| 65 | "SECURE192:-RSA:-GROUP-FFDHE4096:-GROUP-FFDHE6144:-GROUP-FFDHE8192:+GROUP-X25519:%SERVER_" |
| 66 | "PRECEDENCE:%SAFE_RENEGOTIATION"}; |
| 67 | static constexpr const char* TLS_FULL_PRIORITY_STRING { |
| 68 | "SECURE192:-KX-ALL:+ANON-ECDH:+ANON-DH:+SECURE192:-RSA:-GROUP-FFDHE4096:-GROUP-FFDHE6144:-" |
| 69 | "GROUP-FFDHE8192:+GROUP-X25519:%SERVER_PRECEDENCE:%SAFE_RENEGOTIATION"}; |
| 70 | static constexpr uint32_t RX_MAX_SIZE {64 * 1024}; // 64k = max size of a UDP packet |
| 71 | static constexpr std::size_t INPUT_MAX_SIZE { |
| 72 | 1000}; // Maximum number of packets to store before dropping (pkt size = DTLS_MTU) |
| 73 | static constexpr ssize_t FLOOD_THRESHOLD {4 * 1024}; |
| 74 | static constexpr auto FLOOD_PAUSE = std::chrono::milliseconds( |
| 75 | 100); // Time to wait after an invalid cookie packet (anti flood attack) |
| 76 | static constexpr size_t HANDSHAKE_MAX_RETRY {64}; |
| 77 | static constexpr auto DTLS_RETRANSMIT_TIMEOUT = std::chrono::milliseconds( |
| 78 | 1000); // Delay between two handshake request on DTLS |
| 79 | static constexpr auto COOKIE_TIMEOUT = std::chrono::seconds( |
| 80 | 10); // Time to wait for a cookie packet from client |
| 81 | static constexpr int MIN_MTU { |
| 82 | 512 - 20 - 8}; // minimal payload size of a DTLS packet carried by an IPv4 packet |
| 83 | static constexpr uint8_t HEARTBEAT_TRIES = 1; // Number of tries at each heartbeat ping send |
| 84 | static constexpr auto HEARTBEAT_RETRANS_TIMEOUT = std::chrono::milliseconds( |
| 85 | 700); // gnutls heartbeat retransmission timeout for each ping (in milliseconds) |
| 86 | static constexpr auto HEARTBEAT_TOTAL_TIMEOUT |
| 87 | = HEARTBEAT_RETRANS_TIMEOUT |
| 88 | * HEARTBEAT_TRIES; // gnutls heartbeat time limit for heartbeat procedure (in milliseconds) |
| 89 | static constexpr int MISS_ORDERING_LIMIT |
| 90 | = 32; // maximal accepted distance of out-of-order packet (note: must be a signed type) |
| 91 | static constexpr auto RX_OOO_TIMEOUT = std::chrono::milliseconds(1500); |
| 92 | static constexpr int ASYMETRIC_TRANSPORT_MTU_OFFSET |
| 93 | = 20; // when client, if your local IP is IPV4 and server is IPV6; you must reduce your MTU to |
| 94 | // avoid packet too big error on server side. the offset is the difference in size of IP headers |
| 95 | static constexpr auto OCSP_REQUEST_TIMEOUT = std::chrono::seconds( |
| 96 | 2); // Time to wait for an ocsp-request |
| 97 | |
| 98 | // Helper to cast any duration into an integer number of milliseconds |
| 99 | template<class Rep, class Period> |
| 100 | static std::chrono::milliseconds::rep |
| 101 | duration2ms(std::chrono::duration<Rep, Period> d) |
| 102 | { |
| 103 | return std::chrono::duration_cast<std::chrono::milliseconds>(d).count(); |
| 104 | } |
| 105 | |
| 106 | static inline uint64_t |
| 107 | array2uint(const std::array<uint8_t, 8>& a) |
| 108 | { |
| 109 | uint64_t res = 0; |
| 110 | for (int i = 0; i < 8; ++i) |
| 111 | res = (res << 8) + a[i]; |
| 112 | return res; |
| 113 | } |
| 114 | |
| 115 | //============================================================================== |
| 116 | |
| 117 | namespace { |
| 118 | |
| 119 | class TlsCertificateCredendials |
| 120 | { |
| 121 | using T = gnutls_certificate_credentials_t; |
| 122 | |
| 123 | public: |
| 124 | TlsCertificateCredendials() |
| 125 | { |
| 126 | int ret = gnutls_certificate_allocate_credentials(&creds_); |
| 127 | if (ret < 0) { |
| 128 | //if (params_.logger) |
| 129 | // params_.logger->e("gnutls_certificate_allocate_credentials() failed with ret=%d", ret); |
| 130 | throw std::bad_alloc(); |
| 131 | } |
| 132 | } |
| 133 | |
| 134 | ~TlsCertificateCredendials() { gnutls_certificate_free_credentials(creds_); } |
| 135 | |
| 136 | operator T() { return creds_; } |
| 137 | |
| 138 | private: |
| 139 | TlsCertificateCredendials(const TlsCertificateCredendials&) = delete; |
| 140 | TlsCertificateCredendials& operator=(const TlsCertificateCredendials&) = delete; |
| 141 | T creds_; |
| 142 | }; |
| 143 | |
| 144 | class TlsAnonymousClientCredendials |
| 145 | { |
| 146 | using T = gnutls_anon_client_credentials_t; |
| 147 | |
| 148 | public: |
| 149 | TlsAnonymousClientCredendials() |
| 150 | { |
| 151 | int ret = gnutls_anon_allocate_client_credentials(&creds_); |
| 152 | if (ret < 0) { |
| 153 | //if (params_.logger) |
| 154 | // params_.logger->e("gnutls_anon_allocate_client_credentials() failed with ret=%d", ret); |
| 155 | throw std::bad_alloc(); |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | ~TlsAnonymousClientCredendials() { gnutls_anon_free_client_credentials(creds_); } |
| 160 | |
| 161 | operator T() { return creds_; } |
| 162 | |
| 163 | private: |
| 164 | TlsAnonymousClientCredendials(const TlsAnonymousClientCredendials&) = delete; |
| 165 | TlsAnonymousClientCredendials& operator=(const TlsAnonymousClientCredendials&) = delete; |
| 166 | T creds_; |
| 167 | }; |
| 168 | |
| 169 | class TlsAnonymousServerCredendials |
| 170 | { |
| 171 | using T = gnutls_anon_server_credentials_t; |
| 172 | |
| 173 | public: |
| 174 | TlsAnonymousServerCredendials() |
| 175 | { |
| 176 | int ret = gnutls_anon_allocate_server_credentials(&creds_); |
| 177 | if (ret < 0) { |
| 178 | //if (params_.logger) |
| 179 | // params_.logger->e("gnutls_anon_allocate_server_credentials() failed with ret=%d", ret); |
| 180 | throw std::bad_alloc(); |
| 181 | } |
| 182 | } |
| 183 | |
| 184 | ~TlsAnonymousServerCredendials() { gnutls_anon_free_server_credentials(creds_); } |
| 185 | |
| 186 | operator T() { return creds_; } |
| 187 | |
| 188 | private: |
| 189 | TlsAnonymousServerCredendials(const TlsAnonymousServerCredendials&) = delete; |
| 190 | TlsAnonymousServerCredendials& operator=(const TlsAnonymousServerCredendials&) = delete; |
| 191 | T creds_; |
| 192 | }; |
| 193 | |
| 194 | } // namespace |
| 195 | |
| 196 | //============================================================================== |
| 197 | |
| 198 | class TlsSession::TlsSessionImpl |
| 199 | { |
| 200 | public: |
| 201 | using clock = std::chrono::steady_clock; |
| 202 | using StateHandler = std::function<TlsSessionState(TlsSessionState state)>; |
| 203 | using OcspVerification = std::function<void(const int status)>; |
| 204 | using HttpResponse = std::function<void(const dht::http::Response& response)>; |
| 205 | |
| 206 | // Constants (ctor init.) |
| 207 | const bool isServer_; |
| 208 | const TlsParams params_; |
| 209 | const TlsSessionCallbacks callbacks_; |
| 210 | const bool anonymous_; |
| 211 | |
| 212 | TlsSessionImpl(std::unique_ptr<SocketType>&& transport, |
| 213 | const TlsParams& params, |
| 214 | const TlsSessionCallbacks& cbs, |
| 215 | bool anonymous); |
| 216 | |
| 217 | ~TlsSessionImpl(); |
| 218 | |
| 219 | const char* typeName() const; |
| 220 | |
| 221 | std::unique_ptr<SocketType> transport_; |
| 222 | |
| 223 | // State protectors |
| 224 | std::mutex stateMutex_; |
| 225 | std::condition_variable stateCondition_; |
| 226 | |
| 227 | // State machine |
| 228 | TlsSessionState handleStateSetup(TlsSessionState state); |
| 229 | TlsSessionState handleStateCookie(TlsSessionState state); |
| 230 | TlsSessionState handleStateHandshake(TlsSessionState state); |
| 231 | TlsSessionState handleStateMtuDiscovery(TlsSessionState state); |
| 232 | TlsSessionState handleStateEstablished(TlsSessionState state); |
| 233 | TlsSessionState handleStateShutdown(TlsSessionState state); |
| 234 | std::map<TlsSessionState, StateHandler> fsmHandlers_ {}; |
| 235 | std::atomic<TlsSessionState> state_ {TlsSessionState::SETUP}; |
| 236 | std::atomic<TlsSessionState> newState_ {TlsSessionState::NONE}; |
| 237 | std::atomic<int> maxPayload_ {-1}; |
| 238 | |
| 239 | // IO GnuTLS <-> ICE |
| 240 | std::mutex rxMutex_ {}; |
| 241 | std::condition_variable rxCv_ {}; |
| 242 | std::list<std::vector<ValueType>> rxQueue_ {}; |
| 243 | |
| 244 | bool flushProcessing_ {false}; ///< protect against recursive call to flushRxQueue |
| 245 | std::vector<ValueType> rawPktBuf_; ///< gnutls incoming packet buffer |
| 246 | uint64_t baseSeq_ {0}; ///< sequence number of first application data packet received |
| 247 | uint64_t lastRxSeq_ {0}; ///< last received and valid packet sequence number |
| 248 | uint64_t gapOffset_ {0}; ///< offset of first byte not received yet |
| 249 | clock::time_point lastReadTime_; |
| 250 | std::map<uint64_t, std::vector<ValueType>> reorderBuffer_ {}; |
| 251 | std::list<clock::time_point> nextFlush_ {}; |
| 252 | |
| 253 | std::size_t send(const ValueType*, std::size_t, std::error_code&); |
| 254 | ssize_t sendRaw(const void*, size_t); |
| 255 | ssize_t sendRawVec(const giovec_t*, int); |
| 256 | ssize_t recvRaw(void*, size_t); |
| 257 | int waitForRawData(std::chrono::milliseconds); |
| 258 | |
| 259 | bool initFromRecordState(int offset = 0); |
| 260 | void handleDataPacket(std::vector<ValueType>&&, uint64_t); |
| 261 | void flushRxQueue(std::unique_lock<std::mutex>&); |
| 262 | |
| 263 | // Statistics |
| 264 | std::atomic<std::size_t> stRxRawPacketCnt_ {0}; |
| 265 | std::atomic<std::size_t> stRxRawBytesCnt_ {0}; |
| 266 | std::atomic<std::size_t> stRxRawPacketDropCnt_ {0}; |
| 267 | std::atomic<std::size_t> stTxRawPacketCnt_ {0}; |
| 268 | std::atomic<std::size_t> stTxRawBytesCnt_ {0}; |
| 269 | void dump_io_stats() const; |
| 270 | |
| 271 | std::unique_ptr<TlsAnonymousClientCredendials> cacred_; // ctor init. |
| 272 | std::unique_ptr<TlsAnonymousServerCredendials> sacred_; // ctor init. |
| 273 | std::unique_ptr<TlsCertificateCredendials> xcred_; // ctor init. |
| 274 | std::mutex sessionReadMutex_; |
| 275 | std::mutex sessionWriteMutex_; |
| 276 | gnutls_session_t session_ {nullptr}; |
| 277 | gnutls_datum_t cookie_key_ {nullptr, 0}; |
| 278 | gnutls_dtls_prestate_st prestate_ {}; |
| 279 | ssize_t cookie_count_ {0}; |
| 280 | |
| 281 | TlsSessionState setupClient(); |
| 282 | TlsSessionState setupServer(); |
| 283 | void initAnonymous(); |
| 284 | void initCredentials(); |
| 285 | bool commonSessionInit(); |
| 286 | |
| 287 | std::shared_ptr<dht::crypto::Certificate> peerCertificate(gnutls_session_t session) const; |
| 288 | |
| 289 | /* |
| 290 | * Implicit certificate validations. |
| 291 | */ |
| 292 | int verifyCertificateWrapper(gnutls_session_t session); |
| 293 | /* |
| 294 | * Verify OCSP (Online Certificate Service Protocol): |
| 295 | */ |
| 296 | void verifyOcsp(const std::string& url, |
| 297 | dht::crypto::Certificate& cert, |
| 298 | gnutls_x509_crt_t issuer, |
| 299 | OcspVerification cb); |
| 300 | /* |
| 301 | * Send OCSP Request to the specified URI. |
| 302 | */ |
| 303 | void sendOcspRequest(const std::string& uri, |
| 304 | std::string body, |
| 305 | std::chrono::seconds timeout, |
| 306 | HttpResponse cb = {}); |
| 307 | |
| 308 | // FSM thread (TLS states) |
| 309 | ThreadLoop thread_; // ctor init. |
| 310 | bool setup(); |
| 311 | void process(); |
| 312 | void cleanup(); |
| 313 | |
| 314 | // Path mtu discovery |
| 315 | std::array<int, 3> MTUS_; |
| 316 | int mtuProbe_; |
| 317 | int hbPingRecved_ {0}; |
| 318 | bool pmtudOver_ {false}; |
| 319 | void pathMtuHeartbeat(); |
| 320 | |
| 321 | std::mutex requestsMtx_; |
| 322 | std::set<std::shared_ptr<dht::http::Request>> requests_; |
| 323 | std::shared_ptr<dht::crypto::Certificate> pCert_ {}; |
| 324 | }; |
| 325 | |
| 326 | TlsSession::TlsSessionImpl::TlsSessionImpl(std::unique_ptr<SocketType>&& transport, |
| 327 | const TlsParams& params, |
| 328 | const TlsSessionCallbacks& cbs, |
| 329 | bool anonymous) |
| 330 | : isServer_(not transport->isInitiator()) |
| 331 | , params_(params) |
| 332 | , callbacks_(cbs) |
| 333 | , anonymous_(anonymous) |
| 334 | , transport_ {std::move(transport)} |
| 335 | , cacred_(nullptr) |
| 336 | , sacred_(nullptr) |
| 337 | , xcred_(nullptr) |
| 338 | , thread_(params.logger, [this] { return setup(); }, [this] { process(); }, [this] { cleanup(); }) |
| 339 | { |
| 340 | if (not transport_->isReliable()) { |
| 341 | transport_->setOnRecv([this](const ValueType* buf, size_t len) { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 342 | std::lock_guard lk {rxMutex_}; |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 343 | if (rxQueue_.size() == INPUT_MAX_SIZE) { |
| 344 | rxQueue_.pop_front(); // drop oldest packet if input buffer is full |
| 345 | ++stRxRawPacketDropCnt_; |
| 346 | } |
| 347 | rxQueue_.emplace_back(buf, buf + len); |
| 348 | ++stRxRawPacketCnt_; |
| 349 | stRxRawBytesCnt_ += len; |
| 350 | rxCv_.notify_one(); |
| 351 | return len; |
| 352 | }); |
| 353 | } |
| 354 | |
| 355 | // Run FSM into dedicated thread |
| 356 | thread_.start(); |
| 357 | } |
| 358 | |
| 359 | TlsSession::TlsSessionImpl::~TlsSessionImpl() |
| 360 | { |
| 361 | state_ = TlsSessionState::SHUTDOWN; |
| 362 | stateCondition_.notify_all(); |
| 363 | rxCv_.notify_all(); |
| 364 | { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 365 | std::lock_guard lock(requestsMtx_); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 366 | // requests_ store a shared_ptr, so we need to cancel requests |
| 367 | // to not be stuck in verifyCertificateWrapper |
| 368 | for (auto& request : requests_) |
| 369 | request->cancel(); |
| 370 | requests_.clear(); |
| 371 | } |
| 372 | thread_.join(); |
| 373 | if (not transport_->isReliable()) |
| 374 | transport_->setOnRecv(nullptr); |
| 375 | } |
| 376 | |
| 377 | const char* |
| 378 | TlsSession::TlsSessionImpl::typeName() const |
| 379 | { |
| 380 | return isServer_ ? "server" : "client"; |
| 381 | } |
| 382 | |
| 383 | void |
| 384 | TlsSession::TlsSessionImpl::dump_io_stats() const |
| 385 | { |
| 386 | if (params_.logger) |
| 387 | params_.logger->debug("[TLS] RxRawPkt={:d} ({:d} bytes) - TxRawPkt={:d} ({:d} bytes)", |
| 388 | stRxRawPacketCnt_.load(), |
| 389 | stRxRawBytesCnt_.load(), |
| 390 | stTxRawPacketCnt_.load(), |
| 391 | stTxRawBytesCnt_.load()); |
| 392 | } |
| 393 | |
| 394 | TlsSessionState |
| 395 | TlsSession::TlsSessionImpl::setupClient() |
| 396 | { |
| 397 | int ret; |
| 398 | |
| 399 | if (not transport_->isReliable()) { |
| 400 | ret = gnutls_init(&session_, GNUTLS_CLIENT | GNUTLS_DATAGRAM); |
| 401 | // uncoment to reactivate PMTUD |
| 402 | // if (params_.logger) |
| 403 | params_.logger->d("[TLS] set heartbeat reception for retrocompatibility check on server"); |
| 404 | // gnutls_heartbeat_enable(session_,GNUTLS_HB_PEER_ALLOWED_TO_SEND); |
| 405 | } else { |
| 406 | ret = gnutls_init(&session_, GNUTLS_CLIENT); |
| 407 | } |
| 408 | |
| 409 | if (ret != GNUTLS_E_SUCCESS) { |
| 410 | if (params_.logger) |
| 411 | params_.logger->e("[TLS] session init failed: %s", gnutls_strerror(ret)); |
| 412 | return TlsSessionState::SHUTDOWN; |
| 413 | } |
| 414 | |
| 415 | if (not commonSessionInit()) { |
| 416 | return TlsSessionState::SHUTDOWN; |
| 417 | } |
| 418 | |
| 419 | return TlsSessionState::HANDSHAKE; |
| 420 | } |
| 421 | |
| 422 | TlsSessionState |
| 423 | TlsSession::TlsSessionImpl::setupServer() |
| 424 | { |
| 425 | int ret; |
| 426 | |
| 427 | if (not transport_->isReliable()) { |
| 428 | ret = gnutls_init(&session_, GNUTLS_SERVER | GNUTLS_DATAGRAM); |
| 429 | |
| 430 | // uncoment to reactivate PMTUD |
| 431 | // if (params_.logger) |
| 432 | params_.logger->d("[TLS] set heartbeat reception"); |
| 433 | // gnutls_heartbeat_enable(session_, GNUTLS_HB_PEER_ALLOWED_TO_SEND); |
| 434 | |
| 435 | gnutls_dtls_prestate_set(session_, &prestate_); |
| 436 | } else { |
| 437 | ret = gnutls_init(&session_, GNUTLS_SERVER); |
| 438 | } |
| 439 | |
| 440 | if (ret != GNUTLS_E_SUCCESS) { |
| 441 | if (params_.logger) |
| 442 | params_.logger->e("[TLS] session init failed: %s", gnutls_strerror(ret)); |
| 443 | return TlsSessionState::SHUTDOWN; |
| 444 | } |
| 445 | |
| 446 | gnutls_certificate_server_set_request(session_, GNUTLS_CERT_REQUIRE); |
| 447 | |
| 448 | if (not commonSessionInit()) |
| 449 | return TlsSessionState::SHUTDOWN; |
| 450 | |
| 451 | return TlsSessionState::HANDSHAKE; |
| 452 | } |
| 453 | |
| 454 | void |
| 455 | TlsSession::TlsSessionImpl::initAnonymous() |
| 456 | { |
| 457 | // credentials for handshaking and transmission |
| 458 | if (isServer_) |
| 459 | sacred_.reset(new TlsAnonymousServerCredendials()); |
| 460 | else |
| 461 | cacred_.reset(new TlsAnonymousClientCredendials()); |
| 462 | |
| 463 | // Setup DH-params for anonymous authentification |
| 464 | if (isServer_) { |
| 465 | if (const auto& dh_params = params_.dh_params.get().get()) |
| 466 | gnutls_anon_set_server_dh_params(*sacred_, dh_params); |
| 467 | else |
| 468 | if (params_.logger) |
| 469 | params_.logger->w("[TLS] DH params unavailable"); |
| 470 | } |
| 471 | } |
| 472 | |
| 473 | void |
| 474 | TlsSession::TlsSessionImpl::initCredentials() |
| 475 | { |
| 476 | int ret; |
| 477 | |
| 478 | // credentials for handshaking and transmission |
| 479 | xcred_.reset(new TlsCertificateCredendials()); |
| 480 | |
| 481 | gnutls_certificate_set_verify_function(*xcred_, [](gnutls_session_t session) -> int { |
| 482 | auto this_ = reinterpret_cast<TlsSessionImpl*>(gnutls_session_get_ptr(session)); |
| 483 | return this_->verifyCertificateWrapper(session); |
| 484 | }); |
| 485 | |
| 486 | // Load user-given CA list |
| 487 | if (not params_.ca_list.empty()) { |
| 488 | // Try PEM format first |
| 489 | ret = gnutls_certificate_set_x509_trust_file(*xcred_, |
| 490 | params_.ca_list.c_str(), |
| 491 | GNUTLS_X509_FMT_PEM); |
| 492 | |
| 493 | // Then DER format |
| 494 | if (ret < 0) |
| 495 | ret = gnutls_certificate_set_x509_trust_file(*xcred_, |
| 496 | params_.ca_list.c_str(), |
| 497 | GNUTLS_X509_FMT_DER); |
| 498 | if (ret < 0) |
ovari123 | a15c688 | 2024-09-17 18:34:20 -0400 | [diff] [blame] | 499 | throw std::runtime_error("Unable to load CA " + params_.ca_list + ": " |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 500 | + std::string(gnutls_strerror(ret))); |
| 501 | |
| 502 | if (params_.logger) |
| 503 | params_.logger->d("[TLS] CA list %s loadev", params_.ca_list.c_str()); |
| 504 | } |
| 505 | if (params_.peer_ca) { |
| 506 | auto chain = params_.peer_ca->getChainWithRevocations(); |
| 507 | auto ret = gnutls_certificate_set_x509_trust(*xcred_, |
| 508 | chain.first.data(), |
| 509 | chain.first.size()); |
| 510 | if (not chain.second.empty()) |
| 511 | gnutls_certificate_set_x509_crl(*xcred_, chain.second.data(), chain.second.size()); |
| 512 | if (params_.logger) |
| 513 | params_.logger->debug("[TLS] Peer CA list {:d} ({:d} CRLs): {:d}", |
| 514 | chain.first.size(), |
| 515 | chain.second.size(), |
| 516 | ret); |
| 517 | } |
| 518 | |
| 519 | // Load user-given identity (key and passwd) |
| 520 | if (params_.cert) { |
| 521 | std::vector<gnutls_x509_crt_t> certs; |
| 522 | certs.reserve(3); |
| 523 | auto crt = params_.cert; |
| 524 | while (crt) { |
| 525 | certs.emplace_back(crt->cert); |
| 526 | crt = crt->issuer; |
| 527 | } |
| 528 | |
| 529 | ret = gnutls_certificate_set_x509_key(*xcred_, |
| 530 | certs.data(), |
| 531 | certs.size(), |
| 532 | params_.cert_key->x509_key); |
| 533 | if (ret < 0) |
ovari123 | a15c688 | 2024-09-17 18:34:20 -0400 | [diff] [blame] | 534 | throw std::runtime_error("Unable to load certificate: " + std::string(gnutls_strerror(ret))); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 535 | |
| 536 | if (params_.logger) |
| 537 | params_.logger->d("[TLS] User identity loaded"); |
| 538 | } |
| 539 | |
| 540 | // Setup DH-params (server only, may block on dh_params.get()) |
| 541 | if (isServer_) { |
| 542 | if (const auto& dh_params = params_.dh_params.get().get()) |
| 543 | gnutls_certificate_set_dh_params(*xcred_, dh_params); |
| 544 | else |
| 545 | if (params_.logger) |
| 546 | params_.logger->w("[TLS] DH params unavailable"); // YOMGUI: need to stop? |
| 547 | } |
| 548 | } |
| 549 | |
| 550 | bool |
| 551 | TlsSession::TlsSessionImpl::commonSessionInit() |
| 552 | { |
| 553 | int ret; |
| 554 | |
| 555 | if (anonymous_) { |
| 556 | // Force anonymous connection, see handleStateHandshake how we handle failures |
| 557 | ret = gnutls_priority_set_direct(session_, |
| 558 | transport_->isReliable() ? TLS_FULL_PRIORITY_STRING |
| 559 | : DTLS_FULL_PRIORITY_STRING, |
| 560 | nullptr); |
| 561 | if (ret != GNUTLS_E_SUCCESS) { |
| 562 | if (params_.logger) |
| 563 | params_.logger->e("[TLS] TLS priority set failed: %s", gnutls_strerror(ret)); |
| 564 | return false; |
| 565 | } |
| 566 | |
| 567 | // Add anonymous credentials |
| 568 | if (isServer_) |
| 569 | ret = gnutls_credentials_set(session_, GNUTLS_CRD_ANON, *sacred_); |
| 570 | else |
| 571 | ret = gnutls_credentials_set(session_, GNUTLS_CRD_ANON, *cacred_); |
| 572 | |
| 573 | if (ret != GNUTLS_E_SUCCESS) { |
| 574 | if (params_.logger) |
| 575 | params_.logger->e("[TLS] anonymous credential set failed: %s", gnutls_strerror(ret)); |
| 576 | return false; |
| 577 | } |
| 578 | } else { |
| 579 | // Use a classic non-encrypted CERTIFICATE exchange method (less anonymous) |
| 580 | ret = gnutls_priority_set_direct(session_, |
| 581 | transport_->isReliable() ? TLS_CERT_PRIORITY_STRING |
| 582 | : DTLS_CERT_PRIORITY_STRING, |
| 583 | nullptr); |
| 584 | if (ret != GNUTLS_E_SUCCESS) { |
| 585 | if (params_.logger) |
| 586 | params_.logger->e("[TLS] TLS priority set failed: %s", gnutls_strerror(ret)); |
| 587 | return false; |
| 588 | } |
| 589 | } |
| 590 | |
| 591 | // Add certificate credentials |
| 592 | ret = gnutls_credentials_set(session_, GNUTLS_CRD_CERTIFICATE, *xcred_); |
| 593 | if (ret != GNUTLS_E_SUCCESS) { |
| 594 | if (params_.logger) |
| 595 | params_.logger->e("[TLS] certificate credential set failed: %s", gnutls_strerror(ret)); |
| 596 | return false; |
| 597 | } |
| 598 | gnutls_certificate_send_x509_rdn_sequence(session_, 0); |
| 599 | |
| 600 | if (not transport_->isReliable()) { |
| 601 | // DTLS hanshake timeouts |
| 602 | auto re_tx_timeout = duration2ms(DTLS_RETRANSMIT_TIMEOUT); |
| 603 | gnutls_dtls_set_timeouts(session_, |
| 604 | re_tx_timeout, |
| 605 | std::max(duration2ms(params_.timeout), re_tx_timeout)); |
| 606 | |
| 607 | // gnutls DTLS mtu = maximum payload size given by transport |
| 608 | gnutls_dtls_set_mtu(session_, transport_->maxPayload()); |
| 609 | } |
| 610 | |
| 611 | // Stuff for transport callbacks |
| 612 | gnutls_session_set_ptr(session_, this); |
| 613 | gnutls_transport_set_ptr(session_, this); |
| 614 | gnutls_transport_set_vec_push_function(session_, |
| 615 | [](gnutls_transport_ptr_t t, |
| 616 | const giovec_t* iov, |
| 617 | int iovcnt) -> ssize_t { |
| 618 | auto this_ = reinterpret_cast<TlsSessionImpl*>(t); |
| 619 | return this_->sendRawVec(iov, iovcnt); |
| 620 | }); |
| 621 | gnutls_transport_set_pull_function(session_, |
| 622 | [](gnutls_transport_ptr_t t, void* d, size_t s) -> ssize_t { |
| 623 | auto this_ = reinterpret_cast<TlsSessionImpl*>(t); |
| 624 | return this_->recvRaw(d, s); |
| 625 | }); |
| 626 | gnutls_transport_set_pull_timeout_function(session_, |
| 627 | [](gnutls_transport_ptr_t t, unsigned ms) -> int { |
| 628 | auto this_ = reinterpret_cast<TlsSessionImpl*>(t); |
| 629 | return this_->waitForRawData( |
| 630 | std::chrono::milliseconds(ms)); |
| 631 | }); |
| 632 | // TODO -1 = default else set value |
| 633 | if (transport_->isReliable()) |
| 634 | gnutls_handshake_set_timeout(session_, duration2ms(params_.timeout)); |
| 635 | return true; |
| 636 | } |
| 637 | |
| 638 | std::string |
| 639 | getOcspUrl(gnutls_x509_crt_t cert) |
| 640 | { |
| 641 | int ret; |
| 642 | gnutls_datum_t aia; |
| 643 | unsigned int seq = 0; |
| 644 | do { |
| 645 | // Extracts the Authority Information Access (AIA) extension, see RFC 5280 section 4.2.2.1 |
| 646 | ret = gnutls_x509_crt_get_authority_info_access(cert, seq++, GNUTLS_IA_OCSP_URI, &aia, NULL); |
| 647 | } while (ret < 0 && ret != GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE); |
| 648 | // could also try the issuer if we include ocsp uri into there |
| 649 | if (ret < 0) { |
| 650 | return {}; |
| 651 | } |
| 652 | std::string url((const char*) aia.data, (size_t) aia.size); |
| 653 | gnutls_free(aia.data); |
| 654 | return url; |
| 655 | } |
| 656 | |
| 657 | int |
| 658 | TlsSession::TlsSessionImpl::verifyCertificateWrapper(gnutls_session_t session) |
| 659 | { |
| 660 | // Perform user-set verification first to avoid flooding with ocsp-requests if peer is denied |
| 661 | int verified; |
| 662 | if (callbacks_.verifyCertificate) { |
| 663 | auto this_ = reinterpret_cast<TlsSessionImpl*>(gnutls_session_get_ptr(session)); |
| 664 | verified = this_->callbacks_.verifyCertificate(session); |
| 665 | if (verified != GNUTLS_E_SUCCESS) |
| 666 | return verified; |
| 667 | } else { |
| 668 | verified = GNUTLS_E_SUCCESS; |
| 669 | } |
| 670 | /* |
| 671 | * Support only x509 format |
| 672 | */ |
| 673 | if (gnutls_certificate_type_get(session) != GNUTLS_CRT_X509) |
| 674 | return GNUTLS_E_CERTIFICATE_ERROR; |
| 675 | |
| 676 | pCert_ = peerCertificate(session); |
| 677 | if (!pCert_) |
| 678 | return GNUTLS_E_CERTIFICATE_ERROR; |
| 679 | |
| 680 | std::string ocspUrl = getOcspUrl(pCert_->cert); |
| 681 | if (ocspUrl.empty()) { |
| 682 | // Skipping OCSP verification: AIA not found |
| 683 | return verified; |
| 684 | } |
| 685 | |
| 686 | // OCSP (Online Certificate Service Protocol) { |
| 687 | std::promise<int> v; |
| 688 | std::future<int> f = v.get_future(); |
| 689 | |
| 690 | gnutls_x509_crt_t issuer_crt = pCert_->issuer ? pCert_->issuer->cert : nullptr; |
| 691 | verifyOcsp(ocspUrl, *pCert_, issuer_crt, [&](const int status) { |
| 692 | if (status == GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE) { |
| 693 | // OCSP URI is absent, don't fail the verification by overwritting the user-set one. |
| 694 | if (params_.logger) |
| 695 | params_.logger->w("Skipping OCSP verification %s: request failed", pCert_->getUID().c_str()); |
| 696 | v.set_value(verified); |
| 697 | } else { |
| 698 | if (status != GNUTLS_E_SUCCESS) { |
| 699 | if (params_.logger) |
| 700 | params_.logger->e("OCSP verification failed for %s: %s (%i)", |
| 701 | pCert_->getUID().c_str(), |
| 702 | gnutls_strerror(status), |
| 703 | status); |
| 704 | } |
| 705 | v.set_value(status); |
| 706 | } |
| 707 | }); |
| 708 | f.wait(); |
| 709 | |
| 710 | return f.get(); |
| 711 | } |
| 712 | |
| 713 | void |
| 714 | TlsSession::TlsSessionImpl::verifyOcsp(const std::string& aia_uri, |
| 715 | dht::crypto::Certificate& cert, |
| 716 | gnutls_x509_crt_t issuer, |
| 717 | OcspVerification cb) |
| 718 | { |
| 719 | if (params_.logger) |
| 720 | params_.logger->d("Certificate's AIA URI: %s", aia_uri.c_str()); |
| 721 | |
| 722 | // Generate OCSP request |
| 723 | std::pair<std::string, dht::Blob> ocsp_req; |
| 724 | try { |
| 725 | ocsp_req = cert.generateOcspRequest(issuer); |
| 726 | } catch (dht::crypto::CryptoException& e) { |
| 727 | if (params_.logger) |
| 728 | params_.logger->e("Failed to generate OCSP request: %s", e.what()); |
| 729 | if (cb) |
| 730 | cb(GNUTLS_E_INVALID_REQUEST); |
| 731 | return; |
| 732 | } |
| 733 | |
| 734 | sendOcspRequest(aia_uri, |
| 735 | std::move(ocsp_req.first), |
| 736 | OCSP_REQUEST_TIMEOUT, |
| 737 | [cb = std::move(cb), &cert, nonce = std::move(ocsp_req.second), this]( |
| 738 | const dht::http::Response& r) { |
| 739 | // Prepare response data |
| 740 | // Verify response validity |
| 741 | if (r.status_code != 200) { |
| 742 | if (params_.logger) |
| 743 | params_.logger->w("HTTP OCSP Request Failed with code %i", r.status_code); |
| 744 | if (cb) |
| 745 | cb(GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE); |
| 746 | return; |
| 747 | } |
| 748 | if (params_.logger) |
| 749 | params_.logger->d("HTTP OCSP Request done!"); |
| 750 | gnutls_ocsp_cert_status_t verify = GNUTLS_OCSP_CERT_UNKNOWN; |
| 751 | try { |
| 752 | cert.ocspResponse = std::make_shared<dht::crypto::OcspResponse>( |
| 753 | (const uint8_t*) r.body.data(), r.body.size()); |
| 754 | if (params_.logger) |
| 755 | params_.logger->d("%s", cert.ocspResponse->toString().c_str()); |
| 756 | verify = cert.ocspResponse->verifyDirect(cert, nonce); |
| 757 | } catch (dht::crypto::CryptoException& e) { |
| 758 | if (params_.logger) |
| 759 | params_.logger->e("Failed to verify OCSP response: %s", e.what()); |
| 760 | } |
| 761 | if (verify == GNUTLS_OCSP_CERT_UNKNOWN) { |
| 762 | // Soft-fail |
| 763 | if (cb) |
| 764 | cb(GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE); |
| 765 | return; |
| 766 | } |
| 767 | int status = GNUTLS_E_SUCCESS; |
| 768 | if (verify == GNUTLS_OCSP_CERT_GOOD) { |
| 769 | if (params_.logger) |
| 770 | params_.logger->d("OCSP verification success!"); |
| 771 | } else { |
| 772 | status = GNUTLS_E_CERTIFICATE_ERROR; |
| 773 | if (params_.logger) |
| 774 | params_.logger->e("OCSP verification: certificate is revoked!"); |
| 775 | } |
| 776 | // Save response into the certificate store |
| 777 | try { |
| 778 | params_.certStore.pinOcspResponse(cert); |
| 779 | } catch (std::exception& e) { |
| 780 | if (params_.logger) |
| 781 | params_.logger->error("{}", e.what()); |
| 782 | } |
| 783 | if (cb) |
| 784 | cb(status); |
| 785 | }); |
| 786 | } |
| 787 | |
| 788 | void |
| 789 | TlsSession::TlsSessionImpl::sendOcspRequest(const std::string& uri, |
| 790 | std::string body, |
| 791 | std::chrono::seconds timeout, |
| 792 | HttpResponse cb) |
| 793 | { |
| 794 | using namespace dht; |
| 795 | auto request = std::make_shared<http::Request>(*params_.io_context, |
| 796 | uri); //, logger); |
| 797 | request->set_method(restinio::http_method_post()); |
| 798 | request->set_header_field(restinio::http_field_t::user_agent, "Jami"); |
| 799 | request->set_header_field(restinio::http_field_t::accept, "*/*"); |
| 800 | request->set_header_field(restinio::http_field_t::content_type, "application/ocsp-request"); |
| 801 | request->set_body(std::move(body)); |
| 802 | request->set_connection_type(restinio::http_connection_header_t::close); |
| 803 | request->timeout(timeout, [request,l=params_.logger](const asio::error_code& ec) { |
| 804 | if (ec and ec != asio::error::operation_aborted) |
| 805 | if (l) l->error("HTTP OCSP Request timeout with error: {:s}", ec.message()); |
| 806 | request->cancel(); |
| 807 | }); |
| 808 | request->add_on_state_change_callback([this, cb = std::move(cb)](const http::Request::State state, |
| 809 | const http::Response response) { |
| 810 | if (params_.logger) |
| 811 | params_.logger->d("HTTP OCSP Request state=%i status_code=%i", |
| 812 | (unsigned int) state, |
| 813 | response.status_code); |
| 814 | if (state != http::Request::State::DONE) |
| 815 | return; |
| 816 | if (cb) |
| 817 | cb(response); |
| 818 | if (auto request = response.request.lock()) { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 819 | std::lock_guard lock(requestsMtx_); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 820 | requests_.erase(request); |
| 821 | } |
| 822 | }); |
| 823 | { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 824 | std::lock_guard lock(requestsMtx_); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 825 | requests_.emplace(request); |
| 826 | } |
| 827 | request->send(); |
| 828 | } |
| 829 | |
| 830 | std::shared_ptr<dht::crypto::Certificate> |
| 831 | TlsSession::TlsSessionImpl::peerCertificate(gnutls_session_t session) const |
| 832 | { |
| 833 | if (!session) |
| 834 | return {}; |
| 835 | /* |
| 836 | * Get the peer's raw certificate (chain) as sent by the peer. |
| 837 | * The first certificate in the list is the peer's certificate, following the issuer's cert. etc. |
| 838 | */ |
| 839 | unsigned int cert_list_size = 0; |
| 840 | auto cert_list = gnutls_certificate_get_peers(session, &cert_list_size); |
| 841 | |
| 842 | if (cert_list == nullptr) |
| 843 | return {}; |
| 844 | std::vector<std::pair<uint8_t*, uint8_t*>> crt_data; |
| 845 | crt_data.reserve(cert_list_size); |
| 846 | for (unsigned i = 0; i < cert_list_size; i++) |
| 847 | crt_data.emplace_back(cert_list[i].data, cert_list[i].data + cert_list[i].size); |
| 848 | return std::make_shared<dht::crypto::Certificate>(crt_data); |
| 849 | } |
| 850 | |
| 851 | std::size_t |
| 852 | TlsSession::TlsSessionImpl::send(const ValueType* tx_data, std::size_t tx_size, std::error_code& ec) |
| 853 | { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 854 | std::lock_guard lk(sessionWriteMutex_); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 855 | if (state_ != TlsSessionState::ESTABLISHED) { |
| 856 | ec = std::error_code(GNUTLS_E_INVALID_SESSION, std::system_category()); |
| 857 | return 0; |
| 858 | } |
| 859 | |
| 860 | std::size_t total_written = 0; |
| 861 | std::size_t max_tx_sz; |
| 862 | |
| 863 | if (transport_->isReliable()) |
| 864 | max_tx_sz = tx_size; |
| 865 | else |
| 866 | max_tx_sz = gnutls_dtls_get_data_mtu(session_); |
| 867 | |
| 868 | // Split incoming data into chunck suitable for the underlying transport |
| 869 | while (total_written < tx_size) { |
| 870 | auto chunck_sz = std::min(max_tx_sz, tx_size - total_written); |
| 871 | auto data_seq = tx_data + total_written; |
| 872 | ssize_t nwritten; |
| 873 | do { |
| 874 | nwritten = gnutls_record_send(session_, data_seq, chunck_sz); |
| 875 | } while ((nwritten == GNUTLS_E_INTERRUPTED and state_ != TlsSessionState::SHUTDOWN) |
| 876 | or nwritten == GNUTLS_E_AGAIN); |
| 877 | if (nwritten < 0) { |
| 878 | /* Normally we would have to retry record_send but our internal |
| 879 | * state has not changed, so we have to ask for more data first. |
| 880 | * We will just try again later, although this should never happen. |
| 881 | */ |
| 882 | if (params_.logger) |
| 883 | params_.logger->error("[TLS] send failed (only {} bytes sent): {}", total_written, gnutls_strerror(nwritten)); |
| 884 | ec = std::error_code(nwritten, std::system_category()); |
| 885 | return 0; |
| 886 | } |
| 887 | |
| 888 | total_written += nwritten; |
| 889 | } |
| 890 | |
| 891 | ec.clear(); |
| 892 | return total_written; |
| 893 | } |
| 894 | |
| 895 | // Called by GNUTLS to send encrypted packet to low-level transport. |
| 896 | // Should return a positive number indicating the bytes sent, and -1 on error. |
| 897 | ssize_t |
| 898 | TlsSession::TlsSessionImpl::sendRaw(const void* buf, size_t size) |
| 899 | { |
| 900 | std::error_code ec; |
| 901 | unsigned retry_count = 0; |
| 902 | do { |
| 903 | auto n = transport_->write(reinterpret_cast<const ValueType*>(buf), size, ec); |
| 904 | if (!ec) { |
| 905 | // log only on success |
| 906 | ++stTxRawPacketCnt_; |
| 907 | stTxRawBytesCnt_ += n; |
| 908 | return n; |
| 909 | } |
| 910 | |
| 911 | if (ec.value() == EAGAIN) { |
| 912 | if (params_.logger) |
Adrien Béraud | 46d6286 | 2023-08-15 12:03:50 -0400 | [diff] [blame] | 913 | params_.logger->warn("[TLS] EAGAIN from transport, retry#{:d}", ++retry_count); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 914 | std::this_thread::sleep_for(std::chrono::milliseconds(10)); |
| 915 | if (retry_count == 100) { |
| 916 | if (params_.logger) |
| 917 | params_.logger->e("[TLS] excessive retry detected, aborting"); |
| 918 | ec.assign(EIO, std::system_category()); |
| 919 | } |
| 920 | } |
| 921 | } while (ec.value() == EAGAIN); |
| 922 | |
| 923 | // Must be called to pass errno value to GnuTLS on Windows (cf. GnuTLS doc) |
| 924 | gnutls_transport_set_errno(session_, ec.value()); |
| 925 | if (params_.logger) |
Adrien Béraud | 46d6286 | 2023-08-15 12:03:50 -0400 | [diff] [blame] | 926 | params_.logger->error("[TLS] transport failure on tx: errno = {:d}: {:s}", ec.value(), strerror(ec.value())); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 927 | return -1; |
| 928 | } |
| 929 | |
| 930 | // Called by GNUTLS to send encrypted packet to low-level transport. |
| 931 | // Should return a positive number indicating the bytes sent, and -1 on error. |
| 932 | ssize_t |
| 933 | TlsSession::TlsSessionImpl::sendRawVec(const giovec_t* iov, int iovcnt) |
| 934 | { |
| 935 | ssize_t sent = 0; |
| 936 | for (int i = 0; i < iovcnt; ++i) { |
| 937 | const giovec_t& dat = iov[i]; |
| 938 | ssize_t ret = sendRaw(dat.iov_base, dat.iov_len); |
| 939 | if (ret < 0) |
| 940 | return -1; |
| 941 | sent += ret; |
| 942 | } |
| 943 | return sent; |
| 944 | } |
| 945 | |
| 946 | // Called by GNUTLS to receive encrypted packet from low-level transport. |
| 947 | // Should return 0 on connection termination, |
| 948 | // a positive number indicating the number of bytes received, |
| 949 | // and -1 on error. |
| 950 | ssize_t |
| 951 | TlsSession::TlsSessionImpl::recvRaw(void* buf, size_t size) |
| 952 | { |
| 953 | if (transport_->isReliable()) { |
| 954 | std::error_code ec; |
| 955 | auto count = transport_->read(reinterpret_cast<ValueType*>(buf), size, ec); |
| 956 | if (!ec) |
| 957 | return count; |
| 958 | gnutls_transport_set_errno(session_, ec.value()); |
| 959 | return -1; |
| 960 | } |
| 961 | |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 962 | std::lock_guard lk {rxMutex_}; |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 963 | if (rxQueue_.empty()) { |
| 964 | gnutls_transport_set_errno(session_, EAGAIN); |
| 965 | return -1; |
| 966 | } |
| 967 | |
| 968 | const auto& pkt = rxQueue_.front(); |
| 969 | const std::size_t count = std::min(pkt.size(), size); |
| 970 | std::copy_n(pkt.begin(), count, reinterpret_cast<ValueType*>(buf)); |
| 971 | rxQueue_.pop_front(); |
| 972 | return count; |
| 973 | } |
| 974 | |
| 975 | // Called by GNUTLS to wait for encrypted packet from low-level transport. |
| 976 | // 'timeout' is in milliseconds. |
| 977 | // Should return 0 on timeout, a positive number if data are available for read, or -1 on error. |
| 978 | int |
| 979 | TlsSession::TlsSessionImpl::waitForRawData(std::chrono::milliseconds timeout) |
| 980 | { |
| 981 | if (transport_->isReliable()) { |
| 982 | std::error_code ec; |
| 983 | auto err = transport_->waitForData(timeout, ec); |
| 984 | if (err <= 0) { |
| 985 | // shutdown? |
| 986 | if (state_ == TlsSessionState::SHUTDOWN) { |
| 987 | gnutls_transport_set_errno(session_, EINTR); |
| 988 | return -1; |
| 989 | } |
| 990 | if (ec) { |
| 991 | gnutls_transport_set_errno(session_, ec.value()); |
| 992 | return -1; |
| 993 | } |
| 994 | return 0; |
| 995 | } |
| 996 | return 1; |
| 997 | } |
| 998 | |
| 999 | // non-reliable uses callback installed with setOnRecv() |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1000 | std::unique_lock lk {rxMutex_}; |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1001 | rxCv_.wait_for(lk, timeout, [this] { |
| 1002 | return !rxQueue_.empty() or state_ == TlsSessionState::SHUTDOWN; |
| 1003 | }); |
| 1004 | if (state_ == TlsSessionState::SHUTDOWN) { |
| 1005 | gnutls_transport_set_errno(session_, EINTR); |
| 1006 | return -1; |
| 1007 | } |
| 1008 | if (rxQueue_.empty()) { |
| 1009 | if (params_.logger) |
| 1010 | params_.logger->error("[TLS] waitForRawData: timeout after {}", timeout); |
| 1011 | return 0; |
| 1012 | } |
| 1013 | return 1; |
| 1014 | } |
| 1015 | |
| 1016 | bool |
| 1017 | TlsSession::TlsSessionImpl::initFromRecordState(int offset) |
| 1018 | { |
| 1019 | std::array<uint8_t, 8> seq; |
| 1020 | if (gnutls_record_get_state(session_, 1, nullptr, nullptr, nullptr, &seq[0]) |
| 1021 | != GNUTLS_E_SUCCESS) { |
| 1022 | if (params_.logger) |
| 1023 | params_.logger->e("[TLS] Fatal-error Unable to read initial state"); |
| 1024 | return false; |
| 1025 | } |
| 1026 | |
| 1027 | baseSeq_ = array2uint(seq) + offset; |
| 1028 | gapOffset_ = baseSeq_; |
| 1029 | lastRxSeq_ = baseSeq_ - 1; |
| 1030 | if (params_.logger) |
| 1031 | params_.logger->debug("[TLS] Initial sequence number: {:d}", baseSeq_); |
| 1032 | return true; |
| 1033 | } |
| 1034 | |
| 1035 | bool |
| 1036 | TlsSession::TlsSessionImpl::setup() |
| 1037 | { |
| 1038 | // Setup FSM |
| 1039 | fsmHandlers_[TlsSessionState::SETUP] = [this](TlsSessionState s) { |
| 1040 | return handleStateSetup(s); |
| 1041 | }; |
| 1042 | fsmHandlers_[TlsSessionState::COOKIE] = [this](TlsSessionState s) { |
| 1043 | return handleStateCookie(s); |
| 1044 | }; |
| 1045 | fsmHandlers_[TlsSessionState::HANDSHAKE] = [this](TlsSessionState s) { |
| 1046 | return handleStateHandshake(s); |
| 1047 | }; |
| 1048 | fsmHandlers_[TlsSessionState::MTU_DISCOVERY] = [this](TlsSessionState s) { |
| 1049 | return handleStateMtuDiscovery(s); |
| 1050 | }; |
| 1051 | fsmHandlers_[TlsSessionState::ESTABLISHED] = [this](TlsSessionState s) { |
| 1052 | return handleStateEstablished(s); |
| 1053 | }; |
| 1054 | fsmHandlers_[TlsSessionState::SHUTDOWN] = [this](TlsSessionState s) { |
| 1055 | return handleStateShutdown(s); |
| 1056 | }; |
| 1057 | |
| 1058 | return true; |
| 1059 | } |
| 1060 | |
| 1061 | void |
| 1062 | TlsSession::TlsSessionImpl::cleanup() |
| 1063 | { |
| 1064 | state_ = TlsSessionState::SHUTDOWN; // be sure to block any user operations |
| 1065 | stateCondition_.notify_all(); |
| 1066 | |
| 1067 | { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1068 | std::lock_guard lk1(sessionReadMutex_); |
| 1069 | std::lock_guard lk2(sessionWriteMutex_); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1070 | if (session_) { |
| 1071 | if (transport_->isReliable()) |
| 1072 | gnutls_bye(session_, GNUTLS_SHUT_RDWR); |
| 1073 | else |
| 1074 | gnutls_bye(session_, GNUTLS_SHUT_WR); // not wait for a peer answer |
| 1075 | gnutls_deinit(session_); |
| 1076 | session_ = nullptr; |
| 1077 | } |
| 1078 | } |
| 1079 | |
| 1080 | if (cookie_key_.data) |
| 1081 | gnutls_free(cookie_key_.data); |
| 1082 | |
| 1083 | transport_->shutdown(); |
| 1084 | } |
| 1085 | |
| 1086 | TlsSessionState |
| 1087 | TlsSession::TlsSessionImpl::handleStateSetup([[maybe_unused]] TlsSessionState state) |
| 1088 | { |
| 1089 | if (params_.logger) |
| 1090 | params_.logger->d("[TLS] Start %s session", typeName()); |
| 1091 | |
| 1092 | try { |
| 1093 | if (anonymous_) |
| 1094 | initAnonymous(); |
| 1095 | initCredentials(); |
| 1096 | } catch (const std::exception& e) { |
| 1097 | if (params_.logger) |
| 1098 | params_.logger->e("[TLS] authentifications init failed: %s", e.what()); |
| 1099 | return TlsSessionState::SHUTDOWN; |
| 1100 | } |
| 1101 | |
| 1102 | if (not isServer_) |
| 1103 | return setupClient(); |
| 1104 | |
| 1105 | // Extra step for DTLS-like transports |
| 1106 | if (transport_ and not transport_->isReliable()) { |
| 1107 | gnutls_key_generate(&cookie_key_, GNUTLS_COOKIE_KEY_SIZE); |
| 1108 | return TlsSessionState::COOKIE; |
| 1109 | } |
| 1110 | return setupServer(); |
| 1111 | } |
| 1112 | |
| 1113 | TlsSessionState |
| 1114 | TlsSession::TlsSessionImpl::handleStateCookie(TlsSessionState state) |
| 1115 | { |
| 1116 | if (params_.logger) |
| 1117 | params_.logger->d("[TLS] SYN cookie"); |
| 1118 | |
| 1119 | std::size_t count; |
| 1120 | { |
| 1121 | // block until rx packet or shutdown |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1122 | std::unique_lock lk {rxMutex_}; |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1123 | if (!rxCv_.wait_for(lk, COOKIE_TIMEOUT, [this] { |
| 1124 | return !rxQueue_.empty() or state_ == TlsSessionState::SHUTDOWN; |
| 1125 | })) { |
| 1126 | if (params_.logger) |
| 1127 | params_.logger->e("[TLS] SYN cookie failed: timeout"); |
| 1128 | return TlsSessionState::SHUTDOWN; |
| 1129 | } |
| 1130 | // Shutdown state? |
| 1131 | if (rxQueue_.empty()) |
| 1132 | return TlsSessionState::SHUTDOWN; |
| 1133 | count = rxQueue_.front().size(); |
| 1134 | } |
| 1135 | |
| 1136 | // Total bytes rx during cookie checking (see flood protection below) |
| 1137 | cookie_count_ += count; |
| 1138 | |
| 1139 | int ret; |
| 1140 | |
| 1141 | // Peek and verify front packet |
| 1142 | { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1143 | std::lock_guard lk {rxMutex_}; |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1144 | auto& pkt = rxQueue_.front(); |
| 1145 | std::memset(&prestate_, 0, sizeof(prestate_)); |
| 1146 | ret = gnutls_dtls_cookie_verify(&cookie_key_, nullptr, 0, pkt.data(), pkt.size(), &prestate_); |
| 1147 | } |
| 1148 | |
| 1149 | if (ret < 0) { |
| 1150 | gnutls_dtls_cookie_send(&cookie_key_, |
| 1151 | nullptr, |
| 1152 | 0, |
| 1153 | &prestate_, |
| 1154 | this, |
| 1155 | [](gnutls_transport_ptr_t t, const void* d, size_t s) -> ssize_t { |
| 1156 | auto this_ = reinterpret_cast<TlsSessionImpl*>(t); |
| 1157 | return this_->sendRaw(d, s); |
| 1158 | }); |
| 1159 | |
| 1160 | // Drop front packet |
| 1161 | { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1162 | std::lock_guard lk {rxMutex_}; |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1163 | rxQueue_.pop_front(); |
| 1164 | } |
| 1165 | |
| 1166 | // Cookie may be sent on multiple network packets |
| 1167 | // So we retry until we get a valid cookie. |
| 1168 | // To protect against a flood attack we delay each retry after FLOOD_THRESHOLD rx bytes. |
| 1169 | if (cookie_count_ >= FLOOD_THRESHOLD) { |
| 1170 | if (params_.logger) |
| 1171 | params_.logger->warn("[TLS] flood threshold reach (retry in {})", FLOOD_PAUSE); |
| 1172 | dump_io_stats(); |
| 1173 | std::this_thread::sleep_for(FLOOD_PAUSE); // flood attack protection |
| 1174 | } |
| 1175 | return state; |
| 1176 | } |
| 1177 | |
| 1178 | if (params_.logger) |
| 1179 | params_.logger->d("[TLS] cookie ok"); |
| 1180 | |
| 1181 | return setupServer(); |
| 1182 | } |
| 1183 | |
| 1184 | TlsSessionState |
| 1185 | TlsSession::TlsSessionImpl::handleStateHandshake(TlsSessionState state) |
| 1186 | { |
| 1187 | int ret; |
| 1188 | size_t retry_count = 0; |
| 1189 | if (params_.logger) |
| 1190 | params_.logger->debug("[TLS] handshake"); |
| 1191 | do { |
| 1192 | ret = gnutls_handshake(session_); |
| 1193 | } while ((ret == GNUTLS_E_INTERRUPTED or ret == GNUTLS_E_AGAIN) |
| 1194 | and ++retry_count < HANDSHAKE_MAX_RETRY |
| 1195 | and state_.load() != TlsSessionState::SHUTDOWN); |
| 1196 | if (retry_count > 0) { |
| 1197 | if (params_.logger) |
| 1198 | params_.logger->error("[TLS] handshake retried count: {}", retry_count); |
| 1199 | } |
| 1200 | |
| 1201 | // Stop on fatal error |
| 1202 | if (gnutls_error_is_fatal(ret) || state_.load() == TlsSessionState::SHUTDOWN) { |
| 1203 | if (params_.logger) |
| 1204 | params_.logger->error("[TLS] handshake failed: {:s}", gnutls_strerror(ret)); |
| 1205 | return TlsSessionState::SHUTDOWN; |
| 1206 | } |
| 1207 | |
| 1208 | // Continue handshaking on non-fatal error |
| 1209 | if (ret != GNUTLS_E_SUCCESS) { |
| 1210 | // TODO: handle GNUTLS_E_LARGE_PACKET (MTU must be lowered) |
| 1211 | if (ret != GNUTLS_E_AGAIN) |
| 1212 | if (params_.logger) |
| 1213 | params_.logger->debug("[TLS] non-fatal handshake error: {:s}", gnutls_strerror(ret)); |
| 1214 | return state; |
| 1215 | } |
| 1216 | |
| 1217 | // Safe-Renegotiation status shall always be true to prevent MiM attack |
| 1218 | // Following https://www.gnutls.org/manual/html_node/Safe-renegotiation.html |
| 1219 | // "Unlike TLS 1.2, the server is not allowed to change identities" |
| 1220 | // So, we don't have to check the status if we are the client |
| 1221 | bool isTLS1_3 = gnutls_protocol_get_version(session_) == GNUTLS_TLS1_3; |
| 1222 | if (!isTLS1_3 || (isTLS1_3 && isServer_)) { |
| 1223 | if (!gnutls_safe_renegotiation_status(session_)) { |
| 1224 | if (params_.logger) |
| 1225 | params_.logger->error("[TLS] server identity changed! MiM attack?"); |
| 1226 | return TlsSessionState::SHUTDOWN; |
| 1227 | } |
| 1228 | } |
| 1229 | |
| 1230 | auto desc = gnutls_session_get_desc(session_); |
| 1231 | if (params_.logger) |
| 1232 | params_.logger->debug("[TLS] session established: {:s}", desc); |
| 1233 | gnutls_free(desc); |
| 1234 | |
| 1235 | // Anonymous connection? rehandshake immediately with certificate authentification forced |
| 1236 | auto cred = gnutls_auth_get_type(session_); |
| 1237 | if (cred == GNUTLS_CRD_ANON) { |
| 1238 | if (params_.logger) |
| 1239 | params_.logger->debug("[TLS] renogotiate with certificate authentification"); |
| 1240 | |
| 1241 | // Re-setup TLS algorithms priority list with only certificate based cipher suites |
| 1242 | ret = gnutls_priority_set_direct(session_, |
| 1243 | transport_ and transport_->isReliable() |
| 1244 | ? TLS_CERT_PRIORITY_STRING |
| 1245 | : DTLS_CERT_PRIORITY_STRING, |
| 1246 | nullptr); |
| 1247 | if (ret != GNUTLS_E_SUCCESS) { |
| 1248 | if (params_.logger) |
| 1249 | params_.logger->error("[TLS] session TLS cert-only priority set failed: {:s}", gnutls_strerror(ret)); |
| 1250 | return TlsSessionState::SHUTDOWN; |
| 1251 | } |
| 1252 | |
| 1253 | // remove anon credentials and re-enable certificate ones |
| 1254 | gnutls_credentials_clear(session_); |
| 1255 | ret = gnutls_credentials_set(session_, GNUTLS_CRD_CERTIFICATE, *xcred_); |
| 1256 | if (ret != GNUTLS_E_SUCCESS) { |
| 1257 | if (params_.logger) |
| 1258 | params_.logger->error("[TLS] session credential set failed: {:s}", gnutls_strerror(ret)); |
| 1259 | return TlsSessionState::SHUTDOWN; |
| 1260 | } |
| 1261 | |
| 1262 | return state; // handshake |
| 1263 | |
| 1264 | } else if (cred != GNUTLS_CRD_CERTIFICATE) { |
| 1265 | if (params_.logger) |
Adrien Béraud | 6de3f88 | 2023-07-06 12:56:29 -0400 | [diff] [blame] | 1266 | params_.logger->error("[TLS] spurious session credential ({})", (int)cred); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1267 | return TlsSessionState::SHUTDOWN; |
| 1268 | } |
| 1269 | |
| 1270 | // Aware about certificates updates |
| 1271 | if (callbacks_.onCertificatesUpdate) { |
| 1272 | unsigned int remote_count; |
| 1273 | auto local = gnutls_certificate_get_ours(session_); |
| 1274 | auto remote = gnutls_certificate_get_peers(session_, &remote_count); |
| 1275 | callbacks_.onCertificatesUpdate(local, remote, remote_count); |
| 1276 | } |
| 1277 | |
| 1278 | return transport_ and transport_->isReliable() ? TlsSessionState::ESTABLISHED |
| 1279 | : TlsSessionState::MTU_DISCOVERY; |
| 1280 | } |
| 1281 | |
| 1282 | TlsSessionState |
| 1283 | TlsSession::TlsSessionImpl::handleStateMtuDiscovery([[maybe_unused]] TlsSessionState state) |
| 1284 | { |
| 1285 | if (!transport_) { |
| 1286 | if (params_.logger) |
| 1287 | params_.logger->w("No transport available when discovering the MTU"); |
| 1288 | return TlsSessionState::SHUTDOWN; |
| 1289 | } |
| 1290 | mtuProbe_ = transport_->maxPayload(); |
| 1291 | assert(mtuProbe_ >= MIN_MTU); |
| 1292 | MTUS_ = {MIN_MTU, std::max((mtuProbe_ + MIN_MTU) / 2, MIN_MTU), mtuProbe_}; |
| 1293 | |
| 1294 | // retrocompatibility check |
| 1295 | if (gnutls_heartbeat_allowed(session_, GNUTLS_HB_LOCAL_ALLOWED_TO_SEND) == 1) { |
| 1296 | if (!isServer_) { |
| 1297 | pathMtuHeartbeat(); |
| 1298 | if (state_ == TlsSessionState::SHUTDOWN) { |
| 1299 | if (params_.logger) |
| 1300 | params_.logger->e("[TLS] session destroyed while performing PMTUD, shuting down"); |
| 1301 | return TlsSessionState::SHUTDOWN; |
| 1302 | } |
| 1303 | pmtudOver_ = true; |
| 1304 | } |
| 1305 | } else { |
| 1306 | if (params_.logger) |
| 1307 | params_.logger->e("[TLS] PEER HEARTBEAT DISABLED: using transport MTU value ", mtuProbe_); |
| 1308 | pmtudOver_ = true; |
| 1309 | } |
| 1310 | |
| 1311 | gnutls_dtls_set_mtu(session_, mtuProbe_); |
| 1312 | maxPayload_ = gnutls_dtls_get_data_mtu(session_); |
| 1313 | |
| 1314 | if (pmtudOver_) { |
| 1315 | if (params_.logger) |
| 1316 | params_.logger->d("[TLS] maxPayload: ", maxPayload_.load()); |
| 1317 | if (!initFromRecordState()) |
| 1318 | return TlsSessionState::SHUTDOWN; |
| 1319 | } |
| 1320 | |
| 1321 | return TlsSessionState::ESTABLISHED; |
| 1322 | } |
| 1323 | |
| 1324 | /* |
| 1325 | * Path MTU discovery heuristic |
| 1326 | * heuristic description: |
| 1327 | * The two members of the current tls connection will exchange dtls heartbeat messages |
| 1328 | * of increasing size until the heartbeat times out which will be considered as a packet |
| 1329 | * drop from the network due to the size of the packet. (one retry to test for a buffer issue) |
| 1330 | * when timeout happens or all the values have been tested, the mtu will be returned. |
| 1331 | * In case of unexpected error the first (and minimal) value of the mtu array |
| 1332 | */ |
| 1333 | void |
| 1334 | TlsSession::TlsSessionImpl::pathMtuHeartbeat() |
| 1335 | { |
| 1336 | if (params_.logger) |
| 1337 | params_.logger->debug("[TLS] PMTUD: starting probing with {} of retransmission timeout", HEARTBEAT_RETRANS_TIMEOUT); |
| 1338 | |
| 1339 | gnutls_heartbeat_set_timeouts(session_, |
| 1340 | HEARTBEAT_RETRANS_TIMEOUT.count(), |
| 1341 | HEARTBEAT_TOTAL_TIMEOUT.count()); |
| 1342 | |
| 1343 | int errno_send = GNUTLS_E_SUCCESS; |
| 1344 | int mtuOffset = 0; |
| 1345 | |
| 1346 | // when the remote (server) has a IPV6 interface selected by ICE, and local (client) has a IPV4 |
| 1347 | // selected, the path MTU discovery triggers errors for packets too big on server side because |
| 1348 | // of different IP headers overhead. Hence we have to signal to the TLS session to reduce the |
| 1349 | // MTU on client size accordingly. |
| 1350 | if (transport_ and transport_->localAddr().isIpv4() and transport_->remoteAddr().isIpv6()) { |
| 1351 | mtuOffset = ASYMETRIC_TRANSPORT_MTU_OFFSET; |
| 1352 | if (params_.logger) |
| 1353 | params_.logger->w("[TLS] local/remote IP protocol version not alike, use an MTU offset of {} bytes to compensate", ASYMETRIC_TRANSPORT_MTU_OFFSET); |
| 1354 | } |
| 1355 | |
| 1356 | mtuProbe_ = MTUS_[0]; |
| 1357 | |
| 1358 | for (auto mtu : MTUS_) { |
| 1359 | gnutls_dtls_set_mtu(session_, mtu); |
| 1360 | auto data_mtu = gnutls_dtls_get_data_mtu(session_); |
| 1361 | if (params_.logger) |
| 1362 | params_.logger->debug("[TLS] PMTUD: mtu {}, payload {}", mtu, data_mtu); |
| 1363 | auto bytesToSend = data_mtu - mtuOffset - 3; // want to know why -3? ask gnutls! |
| 1364 | |
| 1365 | do { |
| 1366 | errno_send = gnutls_heartbeat_ping(session_, |
| 1367 | bytesToSend, |
| 1368 | HEARTBEAT_TRIES, |
| 1369 | GNUTLS_HEARTBEAT_WAIT); |
| 1370 | } while (errno_send == GNUTLS_E_AGAIN |
| 1371 | || (errno_send == GNUTLS_E_INTERRUPTED && state_ != TlsSessionState::SHUTDOWN)); |
| 1372 | |
| 1373 | if (errno_send != GNUTLS_E_SUCCESS) { |
| 1374 | if (params_.logger) |
| 1375 | params_.logger->debug("[TLS] PMTUD: mtu {} [FAILED]", mtu); |
| 1376 | break; |
| 1377 | } |
| 1378 | |
| 1379 | mtuProbe_ = mtu; |
| 1380 | if (params_.logger) |
| 1381 | params_.logger->debug("[TLS] PMTUD: mtu {} [OK]", mtu); |
| 1382 | } |
| 1383 | |
| 1384 | if (errno_send == GNUTLS_E_TIMEDOUT) { // timeout is considered as a packet loss, then the good |
| 1385 | // mtu is the precedent |
| 1386 | if (mtuProbe_ == MTUS_[0]) { |
| 1387 | if (params_.logger) |
| 1388 | params_.logger->warn("[TLS] PMTUD: no response on first ping, using minimal MTU value {}", mtuProbe_); |
| 1389 | } else { |
| 1390 | if (params_.logger) |
| 1391 | params_.logger->warn("[TLS] PMTUD: timed out, using last working mtu {}", mtuProbe_); |
| 1392 | } |
| 1393 | } else if (errno_send != GNUTLS_E_SUCCESS) { |
| 1394 | if (params_.logger) |
| 1395 | params_.logger->error("[TLS] PMTUD: failed with gnutls error '{}'", gnutls_strerror(errno_send)); |
| 1396 | } else { |
| 1397 | if (params_.logger) |
| 1398 | params_.logger->debug("[TLS] PMTUD: reached maximal value"); |
| 1399 | } |
| 1400 | } |
| 1401 | |
| 1402 | void |
| 1403 | TlsSession::TlsSessionImpl::handleDataPacket(std::vector<ValueType>&& buf, uint64_t pkt_seq) |
| 1404 | { |
| 1405 | // Check for a valid seq. num. delta |
| 1406 | int64_t seq_delta = pkt_seq - lastRxSeq_; |
| 1407 | if (seq_delta > 0) { |
| 1408 | lastRxSeq_ = pkt_seq; |
| 1409 | } else { |
| 1410 | // too old? |
| 1411 | if (seq_delta <= -MISS_ORDERING_LIMIT) { |
| 1412 | if (params_.logger) |
| 1413 | params_.logger->warn("[TLS] drop old pkt: 0x{:x}", pkt_seq); |
| 1414 | return; |
| 1415 | } |
| 1416 | |
| 1417 | // No duplicate check as DTLS prevents that for us (replay protection) |
| 1418 | |
| 1419 | // accept Out-Of-Order pkt - will be reordered by queue flush operation |
| 1420 | if (params_.logger) |
| 1421 | params_.logger->warn("[TLS] OOO pkt: 0x{:x}", pkt_seq); |
| 1422 | } |
| 1423 | |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1424 | std::unique_lock lk {rxMutex_}; |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1425 | auto now = clock::now(); |
| 1426 | if (reorderBuffer_.empty()) |
| 1427 | lastReadTime_ = now; |
| 1428 | reorderBuffer_.emplace(pkt_seq, std::move(buf)); |
| 1429 | nextFlush_.emplace_back(now + RX_OOO_TIMEOUT); |
| 1430 | rxCv_.notify_one(); |
| 1431 | // Try to flush right now as a new packet is available |
| 1432 | flushRxQueue(lk); |
| 1433 | } |
| 1434 | |
| 1435 | /// |
| 1436 | /// Reorder and push received packet to upper layer |
| 1437 | /// |
| 1438 | /// \note This method must be called continuously, faster than RX_OOO_TIMEOUT |
| 1439 | /// |
| 1440 | void |
| 1441 | TlsSession::TlsSessionImpl::flushRxQueue(std::unique_lock<std::mutex>& lk) |
| 1442 | { |
| 1443 | // RAII bool swap |
| 1444 | class GuardedBoolSwap |
| 1445 | { |
| 1446 | public: |
| 1447 | explicit GuardedBoolSwap(bool& var) |
| 1448 | : var_ {var} |
| 1449 | { |
| 1450 | var_ = !var_; |
| 1451 | } |
| 1452 | ~GuardedBoolSwap() { var_ = !var_; } |
| 1453 | |
| 1454 | private: |
| 1455 | bool& var_; |
| 1456 | }; |
| 1457 | |
| 1458 | if (reorderBuffer_.empty()) |
| 1459 | return; |
| 1460 | |
| 1461 | // Prevent re-entrant access as the callbacks_.onRxData() is called in unprotected region |
| 1462 | if (flushProcessing_) |
| 1463 | return; |
| 1464 | |
| 1465 | GuardedBoolSwap swap_flush_processing {flushProcessing_}; |
| 1466 | |
| 1467 | auto now = clock::now(); |
| 1468 | |
| 1469 | auto item = std::begin(reorderBuffer_); |
| 1470 | auto next_offset = item->first; |
| 1471 | |
| 1472 | // Wait for next continuous packet until timeout |
| 1473 | if ((now - lastReadTime_) >= RX_OOO_TIMEOUT) { |
| 1474 | // OOO packet timeout - consider waited packets as lost |
| 1475 | if (auto lost = next_offset - gapOffset_) { |
| 1476 | if (params_.logger) |
| 1477 | params_.logger->warn("[TLS] {:d} lost since 0x{:x}", lost, gapOffset_); |
| 1478 | } else if (params_.logger) |
| 1479 | params_.logger->warn("[TLS] slow flush"); |
| 1480 | } else if (next_offset != gapOffset_) |
| 1481 | return; |
| 1482 | |
| 1483 | // Loop on offset-ordered received packet until a discontinuity in sequence number |
| 1484 | while (item != std::end(reorderBuffer_) and item->first <= next_offset) { |
| 1485 | auto pkt_offset = item->first; |
| 1486 | auto pkt = std::move(item->second); |
| 1487 | |
| 1488 | // Remove item before unlocking to not trash the item' relationship |
| 1489 | next_offset = pkt_offset + 1; |
| 1490 | item = reorderBuffer_.erase(item); |
| 1491 | |
| 1492 | if (callbacks_.onRxData) { |
| 1493 | lk.unlock(); |
| 1494 | callbacks_.onRxData(std::move(pkt)); |
| 1495 | lk.lock(); |
| 1496 | } |
| 1497 | } |
| 1498 | |
| 1499 | gapOffset_ = std::max(gapOffset_, next_offset); |
| 1500 | lastReadTime_ = now; |
| 1501 | } |
| 1502 | |
| 1503 | TlsSessionState |
| 1504 | TlsSession::TlsSessionImpl::handleStateEstablished(TlsSessionState state) |
| 1505 | { |
| 1506 | // Nothing to do in reliable mode, so just wait for state change |
| 1507 | if (transport_ and transport_->isReliable()) { |
| 1508 | auto disconnected = [this]() -> bool { |
| 1509 | return state_.load() != TlsSessionState::ESTABLISHED |
| 1510 | or newState_.load() != TlsSessionState::NONE; |
| 1511 | }; |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1512 | std::unique_lock lk(stateMutex_); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1513 | stateCondition_.wait(lk, disconnected); |
| 1514 | auto oldState = state_.load(); |
| 1515 | if (oldState == TlsSessionState::ESTABLISHED) { |
| 1516 | auto newState = newState_.load(); |
| 1517 | if (newState != TlsSessionState::NONE) { |
| 1518 | newState_ = TlsSessionState::NONE; |
| 1519 | return newState; |
| 1520 | } |
| 1521 | } |
| 1522 | return oldState; |
| 1523 | } |
| 1524 | |
| 1525 | // block until rx packet or state change |
| 1526 | { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1527 | std::unique_lock lk {rxMutex_}; |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1528 | if (nextFlush_.empty()) |
| 1529 | rxCv_.wait(lk, [this] { |
| 1530 | return state_ != TlsSessionState::ESTABLISHED or not rxQueue_.empty() |
| 1531 | or not nextFlush_.empty(); |
| 1532 | }); |
| 1533 | else |
| 1534 | rxCv_.wait_until(lk, nextFlush_.front(), [this] { |
| 1535 | return state_ != TlsSessionState::ESTABLISHED or !rxQueue_.empty(); |
| 1536 | }); |
| 1537 | state = state_.load(); |
| 1538 | if (state != TlsSessionState::ESTABLISHED) |
| 1539 | return state; |
| 1540 | |
| 1541 | if (not nextFlush_.empty()) { |
| 1542 | auto now = clock::now(); |
| 1543 | if (nextFlush_.front() <= now) { |
| 1544 | while (nextFlush_.front() <= now) |
| 1545 | nextFlush_.pop_front(); |
| 1546 | flushRxQueue(lk); |
| 1547 | return state; |
| 1548 | } |
| 1549 | } |
| 1550 | } |
| 1551 | |
| 1552 | std::array<uint8_t, 8> seq; |
| 1553 | rawPktBuf_.resize(RX_MAX_SIZE); |
| 1554 | auto ret = gnutls_record_recv_seq(session_, rawPktBuf_.data(), rawPktBuf_.size(), &seq[0]); |
| 1555 | |
| 1556 | if (ret > 0) { |
| 1557 | // Are we in PMTUD phase? |
| 1558 | if (!pmtudOver_) { |
| 1559 | mtuProbe_ = MTUS_[std::max(0, hbPingRecved_ - 1)]; |
| 1560 | gnutls_dtls_set_mtu(session_, mtuProbe_); |
| 1561 | maxPayload_ = gnutls_dtls_get_data_mtu(session_); |
| 1562 | pmtudOver_ = true; |
| 1563 | if (params_.logger) |
| 1564 | params_.logger->debug("[TLS] maxPayload: {}", maxPayload_.load()); |
| 1565 | |
| 1566 | if (!initFromRecordState(-1)) |
| 1567 | return TlsSessionState::SHUTDOWN; |
| 1568 | } |
| 1569 | |
| 1570 | rawPktBuf_.resize(ret); |
| 1571 | handleDataPacket(std::move(rawPktBuf_), array2uint(seq)); |
| 1572 | // no state change |
| 1573 | } else if (ret == GNUTLS_E_HEARTBEAT_PING_RECEIVED) { |
| 1574 | if (params_.logger) |
| 1575 | params_.logger->d("[TLS] PMTUD: ping received sending pong"); |
| 1576 | auto errno_send = gnutls_heartbeat_pong(session_, 0); |
| 1577 | |
| 1578 | if (errno_send != GNUTLS_E_SUCCESS) { |
| 1579 | if (params_.logger) |
| 1580 | params_.logger->e("[TLS] PMTUD: failed on pong with error %d: %s", |
| 1581 | errno_send, |
| 1582 | gnutls_strerror(errno_send)); |
| 1583 | } else { |
| 1584 | ++hbPingRecved_; |
| 1585 | } |
| 1586 | // no state change |
| 1587 | } else if (ret == 0) { |
| 1588 | if (params_.logger) |
| 1589 | params_.logger->d("[TLS] eof"); |
| 1590 | state = TlsSessionState::SHUTDOWN; |
| 1591 | } else if (ret == GNUTLS_E_REHANDSHAKE) { |
| 1592 | if (params_.logger) |
| 1593 | params_.logger->d("[TLS] re-handshake"); |
| 1594 | state = TlsSessionState::HANDSHAKE; |
| 1595 | } else if (gnutls_error_is_fatal(ret)) { |
| 1596 | if (params_.logger) |
| 1597 | params_.logger->e("[TLS] fatal error in recv: %s", gnutls_strerror(ret)); |
| 1598 | state = TlsSessionState::SHUTDOWN; |
| 1599 | } // else non-fatal error... let's continue |
| 1600 | |
| 1601 | return state; |
| 1602 | } |
| 1603 | |
| 1604 | TlsSessionState |
| 1605 | TlsSession::TlsSessionImpl::handleStateShutdown(TlsSessionState state) |
| 1606 | { |
| 1607 | if (params_.logger) |
| 1608 | params_.logger->d("[TLS] shutdown"); |
| 1609 | |
| 1610 | // Stop ourself |
| 1611 | thread_.stop(); |
| 1612 | return state; |
| 1613 | } |
| 1614 | |
| 1615 | void |
| 1616 | TlsSession::TlsSessionImpl::process() |
| 1617 | { |
| 1618 | auto old_state = state_.load(); |
| 1619 | auto new_state = fsmHandlers_[old_state](old_state); |
| 1620 | |
| 1621 | // update state_ with taking care for external state change |
| 1622 | if (not std::atomic_compare_exchange_strong(&state_, &old_state, new_state)) |
| 1623 | new_state = old_state; |
| 1624 | |
| 1625 | if (old_state != new_state) |
| 1626 | stateCondition_.notify_all(); |
| 1627 | |
| 1628 | if (old_state != new_state and callbacks_.onStateChange) |
| 1629 | callbacks_.onStateChange(new_state); |
| 1630 | } |
| 1631 | |
| 1632 | //============================================================================== |
| 1633 | |
| 1634 | TlsSession::TlsSession(std::unique_ptr<SocketType>&& transport, |
| 1635 | const TlsParams& params, |
| 1636 | const TlsSessionCallbacks& cbs, |
| 1637 | bool anonymous) |
| 1638 | |
| 1639 | : pimpl_ {std::make_unique<TlsSessionImpl>(std::move(transport), params, cbs, anonymous)} |
| 1640 | {} |
| 1641 | |
| 1642 | TlsSession::~TlsSession() {} |
| 1643 | |
| 1644 | bool |
| 1645 | TlsSession::isInitiator() const |
| 1646 | { |
| 1647 | return !pimpl_->isServer_; |
| 1648 | } |
| 1649 | |
| 1650 | bool |
| 1651 | TlsSession::isReliable() const |
| 1652 | { |
| 1653 | if (!pimpl_->transport_) |
| 1654 | return false; |
| 1655 | return pimpl_->transport_->isReliable(); |
| 1656 | } |
| 1657 | |
| 1658 | int |
| 1659 | TlsSession::maxPayload() const |
| 1660 | { |
| 1661 | if (pimpl_->state_ == TlsSessionState::SHUTDOWN) |
| 1662 | throw std::runtime_error("Getting maxPayload from non-valid TLS session"); |
| 1663 | if (!pimpl_->transport_) |
| 1664 | return 0; |
| 1665 | return pimpl_->transport_->maxPayload(); |
| 1666 | } |
| 1667 | |
| 1668 | // Called by anyone to stop the connection and the FSM thread |
| 1669 | void |
| 1670 | TlsSession::shutdown() |
| 1671 | { |
| 1672 | pimpl_->newState_ = TlsSessionState::SHUTDOWN; |
| 1673 | pimpl_->stateCondition_.notify_all(); |
| 1674 | pimpl_->rxCv_.notify_one(); // unblock waiting FSM |
| 1675 | } |
| 1676 | |
| 1677 | std::size_t |
| 1678 | TlsSession::write(const ValueType* data, std::size_t size, std::error_code& ec) |
| 1679 | { |
| 1680 | return pimpl_->send(data, size, ec); |
| 1681 | } |
| 1682 | |
| 1683 | std::size_t |
| 1684 | TlsSession::read(ValueType* data, std::size_t size, std::error_code& ec) |
| 1685 | { |
| 1686 | std::errc error; |
| 1687 | |
| 1688 | if (pimpl_->state_ != TlsSessionState::ESTABLISHED) { |
| 1689 | ec = std::make_error_code(std::errc::broken_pipe); |
| 1690 | return 0; |
| 1691 | } |
| 1692 | |
| 1693 | while (true) { |
| 1694 | ssize_t ret; |
| 1695 | { |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1696 | std::lock_guard lk(pimpl_->sessionReadMutex_); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1697 | if (!pimpl_->session_) |
| 1698 | return 0; |
| 1699 | ret = gnutls_record_recv(pimpl_->session_, data, size); |
| 1700 | } |
| 1701 | if (ret > 0) { |
| 1702 | ec.clear(); |
| 1703 | return ret; |
| 1704 | } |
| 1705 | |
Adrien Béraud | 024c46f | 2024-03-02 23:53:18 -0500 | [diff] [blame] | 1706 | std::lock_guard lk(pimpl_->stateMutex_); |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1707 | if (ret == 0) { |
| 1708 | if (pimpl_) { |
| 1709 | if (pimpl_->params_.logger) |
| 1710 | pimpl_->params_.logger->d("[TLS] eof"); |
| 1711 | pimpl_->newState_ = TlsSessionState::SHUTDOWN; |
| 1712 | pimpl_->stateCondition_.notify_all(); |
| 1713 | pimpl_->rxCv_.notify_one(); // unblock waiting FSM |
| 1714 | } |
| 1715 | error = std::errc::broken_pipe; |
| 1716 | break; |
| 1717 | } else if (ret == GNUTLS_E_REHANDSHAKE) { |
| 1718 | if (pimpl_->params_.logger) |
| 1719 | pimpl_->params_.logger->d("[TLS] re-handshake"); |
| 1720 | pimpl_->newState_ = TlsSessionState::HANDSHAKE; |
| 1721 | pimpl_->rxCv_.notify_one(); // unblock waiting FSM |
| 1722 | pimpl_->stateCondition_.notify_all(); |
| 1723 | } else if (gnutls_error_is_fatal(ret)) { |
| 1724 | if (pimpl_ && pimpl_->state_ != TlsSessionState::SHUTDOWN) { |
| 1725 | if (pimpl_->params_.logger) |
| 1726 | pimpl_->params_.logger->e("[TLS] fatal error in recv: %s", gnutls_strerror(ret)); |
| 1727 | pimpl_->newState_ = TlsSessionState::SHUTDOWN; |
| 1728 | pimpl_->stateCondition_.notify_all(); |
| 1729 | pimpl_->rxCv_.notify_one(); // unblock waiting FSM |
| 1730 | } |
| 1731 | error = std::errc::io_error; |
| 1732 | break; |
| 1733 | } |
| 1734 | } |
| 1735 | |
| 1736 | ec = std::make_error_code(error); |
| 1737 | return 0; |
| 1738 | } |
| 1739 | |
Adrien Béraud | 612b55b | 2023-05-29 10:42:04 -0400 | [diff] [blame] | 1740 | int |
| 1741 | TlsSession::waitForData(std::chrono::milliseconds timeout, std::error_code& ec) const |
| 1742 | { |
| 1743 | if (!pimpl_->transport_) { |
| 1744 | ec = std::make_error_code(std::errc::broken_pipe); |
| 1745 | return -1; |
| 1746 | } |
| 1747 | if (!pimpl_->transport_->waitForData(timeout, ec)) |
| 1748 | return 0; |
| 1749 | return 1; |
| 1750 | } |
| 1751 | |
| 1752 | std::shared_ptr<dht::crypto::Certificate> |
| 1753 | TlsSession::peerCertificate() const |
| 1754 | { |
| 1755 | return pimpl_->pCert_; |
| 1756 | } |
| 1757 | |
| 1758 | const std::shared_ptr<dht::log::Logger>& |
| 1759 | TlsSession::logger() const |
| 1760 | { |
| 1761 | return pimpl_->params_.logger; |
| 1762 | } |
| 1763 | |
| 1764 | } // namespace tls |
Sébastien Blin | 464bdff | 2023-07-19 08:02:53 -0400 | [diff] [blame] | 1765 | } // namespace dhtnet |