henrike@webrtc.org | f7795df | 2014-05-13 18:00:26 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2004 The WebRTC Project Authors. All rights reserved. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license |
| 5 | * that can be found in the LICENSE file in the root of the source |
| 6 | * tree. An additional intellectual property rights grant can be found |
| 7 | * in the file PATENTS. All contributing project authors may |
| 8 | * be found in the AUTHORS file in the root of the source tree. |
| 9 | */ |
| 10 | |
| 11 | #if HAVE_CONFIG_H |
| 12 | #include "config.h" |
| 13 | #endif // HAVE_CONFIG_H |
| 14 | |
| 15 | #if HAVE_OPENSSL_SSL_H |
| 16 | |
| 17 | #include "webrtc/base/opensslstreamadapter.h" |
| 18 | |
| 19 | #include <openssl/bio.h> |
| 20 | #include <openssl/crypto.h> |
| 21 | #include <openssl/err.h> |
| 22 | #include <openssl/rand.h> |
| 23 | #include <openssl/x509v3.h> |
| 24 | |
| 25 | #include <vector> |
| 26 | |
| 27 | #include "webrtc/base/common.h" |
| 28 | #include "webrtc/base/logging.h" |
| 29 | #include "webrtc/base/stream.h" |
| 30 | #include "webrtc/base/openssl.h" |
| 31 | #include "webrtc/base/openssladapter.h" |
| 32 | #include "webrtc/base/openssldigest.h" |
| 33 | #include "webrtc/base/opensslidentity.h" |
| 34 | #include "webrtc/base/stringutils.h" |
| 35 | #include "webrtc/base/thread.h" |
| 36 | |
| 37 | namespace rtc { |
| 38 | |
| 39 | #if (OPENSSL_VERSION_NUMBER >= 0x10001000L) |
| 40 | #define HAVE_DTLS_SRTP |
| 41 | #endif |
| 42 | |
| 43 | #ifdef HAVE_DTLS_SRTP |
| 44 | // SRTP cipher suite table |
| 45 | struct SrtpCipherMapEntry { |
| 46 | const char* external_name; |
| 47 | const char* internal_name; |
| 48 | }; |
| 49 | |
| 50 | // This isn't elegant, but it's better than an external reference |
| 51 | static SrtpCipherMapEntry SrtpCipherMap[] = { |
| 52 | {"AES_CM_128_HMAC_SHA1_80", "SRTP_AES128_CM_SHA1_80"}, |
| 53 | {"AES_CM_128_HMAC_SHA1_32", "SRTP_AES128_CM_SHA1_32"}, |
| 54 | {NULL, NULL} |
| 55 | }; |
| 56 | #endif |
| 57 | |
| 58 | ////////////////////////////////////////////////////////////////////// |
| 59 | // StreamBIO |
| 60 | ////////////////////////////////////////////////////////////////////// |
| 61 | |
| 62 | static int stream_write(BIO* h, const char* buf, int num); |
| 63 | static int stream_read(BIO* h, char* buf, int size); |
| 64 | static int stream_puts(BIO* h, const char* str); |
| 65 | static long stream_ctrl(BIO* h, int cmd, long arg1, void* arg2); |
| 66 | static int stream_new(BIO* h); |
| 67 | static int stream_free(BIO* data); |
| 68 | |
| 69 | static BIO_METHOD methods_stream = { |
| 70 | BIO_TYPE_BIO, |
| 71 | "stream", |
| 72 | stream_write, |
| 73 | stream_read, |
| 74 | stream_puts, |
| 75 | 0, |
| 76 | stream_ctrl, |
| 77 | stream_new, |
| 78 | stream_free, |
| 79 | NULL, |
| 80 | }; |
| 81 | |
| 82 | static BIO_METHOD* BIO_s_stream() { return(&methods_stream); } |
| 83 | |
| 84 | static BIO* BIO_new_stream(StreamInterface* stream) { |
| 85 | BIO* ret = BIO_new(BIO_s_stream()); |
| 86 | if (ret == NULL) |
| 87 | return NULL; |
| 88 | ret->ptr = stream; |
| 89 | return ret; |
| 90 | } |
| 91 | |
| 92 | // bio methods return 1 (or at least non-zero) on success and 0 on failure. |
| 93 | |
| 94 | static int stream_new(BIO* b) { |
| 95 | b->shutdown = 0; |
| 96 | b->init = 1; |
| 97 | b->num = 0; // 1 means end-of-stream |
| 98 | b->ptr = 0; |
| 99 | return 1; |
| 100 | } |
| 101 | |
| 102 | static int stream_free(BIO* b) { |
| 103 | if (b == NULL) |
| 104 | return 0; |
| 105 | return 1; |
| 106 | } |
| 107 | |
| 108 | static int stream_read(BIO* b, char* out, int outl) { |
| 109 | if (!out) |
| 110 | return -1; |
| 111 | StreamInterface* stream = static_cast<StreamInterface*>(b->ptr); |
| 112 | BIO_clear_retry_flags(b); |
| 113 | size_t read; |
| 114 | int error; |
| 115 | StreamResult result = stream->Read(out, outl, &read, &error); |
| 116 | if (result == SR_SUCCESS) { |
| 117 | return read; |
| 118 | } else if (result == SR_EOS) { |
| 119 | b->num = 1; |
| 120 | } else if (result == SR_BLOCK) { |
| 121 | BIO_set_retry_read(b); |
| 122 | } |
| 123 | return -1; |
| 124 | } |
| 125 | |
| 126 | static int stream_write(BIO* b, const char* in, int inl) { |
| 127 | if (!in) |
| 128 | return -1; |
| 129 | StreamInterface* stream = static_cast<StreamInterface*>(b->ptr); |
| 130 | BIO_clear_retry_flags(b); |
| 131 | size_t written; |
| 132 | int error; |
| 133 | StreamResult result = stream->Write(in, inl, &written, &error); |
| 134 | if (result == SR_SUCCESS) { |
| 135 | return written; |
| 136 | } else if (result == SR_BLOCK) { |
| 137 | BIO_set_retry_write(b); |
| 138 | } |
| 139 | return -1; |
| 140 | } |
| 141 | |
| 142 | static int stream_puts(BIO* b, const char* str) { |
| 143 | return stream_write(b, str, strlen(str)); |
| 144 | } |
| 145 | |
| 146 | static long stream_ctrl(BIO* b, int cmd, long num, void* ptr) { |
| 147 | UNUSED(num); |
| 148 | UNUSED(ptr); |
| 149 | |
| 150 | switch (cmd) { |
| 151 | case BIO_CTRL_RESET: |
| 152 | return 0; |
| 153 | case BIO_CTRL_EOF: |
| 154 | return b->num; |
| 155 | case BIO_CTRL_WPENDING: |
| 156 | case BIO_CTRL_PENDING: |
| 157 | return 0; |
| 158 | case BIO_CTRL_FLUSH: |
| 159 | return 1; |
| 160 | default: |
| 161 | return 0; |
| 162 | } |
| 163 | } |
| 164 | |
| 165 | ///////////////////////////////////////////////////////////////////////////// |
| 166 | // OpenSSLStreamAdapter |
| 167 | ///////////////////////////////////////////////////////////////////////////// |
| 168 | |
| 169 | OpenSSLStreamAdapter::OpenSSLStreamAdapter(StreamInterface* stream) |
| 170 | : SSLStreamAdapter(stream), |
| 171 | state_(SSL_NONE), |
| 172 | role_(SSL_CLIENT), |
| 173 | ssl_read_needs_write_(false), ssl_write_needs_read_(false), |
| 174 | ssl_(NULL), ssl_ctx_(NULL), |
| 175 | custom_verification_succeeded_(false), |
| 176 | ssl_mode_(SSL_MODE_TLS) { |
| 177 | } |
| 178 | |
| 179 | OpenSSLStreamAdapter::~OpenSSLStreamAdapter() { |
| 180 | Cleanup(); |
| 181 | } |
| 182 | |
| 183 | void OpenSSLStreamAdapter::SetIdentity(SSLIdentity* identity) { |
| 184 | ASSERT(!identity_); |
| 185 | identity_.reset(static_cast<OpenSSLIdentity*>(identity)); |
| 186 | } |
| 187 | |
| 188 | void OpenSSLStreamAdapter::SetServerRole(SSLRole role) { |
| 189 | role_ = role; |
| 190 | } |
| 191 | |
| 192 | bool OpenSSLStreamAdapter::GetPeerCertificate(SSLCertificate** cert) const { |
| 193 | if (!peer_certificate_) |
| 194 | return false; |
| 195 | |
| 196 | *cert = peer_certificate_->GetReference(); |
| 197 | return true; |
| 198 | } |
| 199 | |
| 200 | bool OpenSSLStreamAdapter::SetPeerCertificateDigest(const std::string |
| 201 | &digest_alg, |
| 202 | const unsigned char* |
| 203 | digest_val, |
| 204 | size_t digest_len) { |
| 205 | ASSERT(!peer_certificate_); |
| 206 | ASSERT(peer_certificate_digest_algorithm_.size() == 0); |
| 207 | ASSERT(ssl_server_name_.empty()); |
| 208 | size_t expected_len; |
| 209 | |
| 210 | if (!OpenSSLDigest::GetDigestSize(digest_alg, &expected_len)) { |
| 211 | LOG(LS_WARNING) << "Unknown digest algorithm: " << digest_alg; |
| 212 | return false; |
| 213 | } |
| 214 | if (expected_len != digest_len) |
| 215 | return false; |
| 216 | |
| 217 | peer_certificate_digest_value_.SetData(digest_val, digest_len); |
| 218 | peer_certificate_digest_algorithm_ = digest_alg; |
| 219 | |
| 220 | return true; |
| 221 | } |
| 222 | |
| 223 | // Key Extractor interface |
| 224 | bool OpenSSLStreamAdapter::ExportKeyingMaterial(const std::string& label, |
| 225 | const uint8* context, |
| 226 | size_t context_len, |
| 227 | bool use_context, |
| 228 | uint8* result, |
| 229 | size_t result_len) { |
| 230 | #ifdef HAVE_DTLS_SRTP |
| 231 | int i; |
| 232 | |
| 233 | i = SSL_export_keying_material(ssl_, result, result_len, |
| 234 | label.c_str(), label.length(), |
| 235 | const_cast<uint8 *>(context), |
| 236 | context_len, use_context); |
| 237 | |
| 238 | if (i != 1) |
| 239 | return false; |
| 240 | |
| 241 | return true; |
| 242 | #else |
| 243 | return false; |
| 244 | #endif |
| 245 | } |
| 246 | |
| 247 | bool OpenSSLStreamAdapter::SetDtlsSrtpCiphers( |
| 248 | const std::vector<std::string>& ciphers) { |
| 249 | #ifdef HAVE_DTLS_SRTP |
| 250 | std::string internal_ciphers; |
| 251 | |
| 252 | if (state_ != SSL_NONE) |
| 253 | return false; |
| 254 | |
| 255 | for (std::vector<std::string>::const_iterator cipher = ciphers.begin(); |
| 256 | cipher != ciphers.end(); ++cipher) { |
| 257 | bool found = false; |
| 258 | for (SrtpCipherMapEntry *entry = SrtpCipherMap; entry->internal_name; |
| 259 | ++entry) { |
| 260 | if (*cipher == entry->external_name) { |
| 261 | found = true; |
| 262 | if (!internal_ciphers.empty()) |
| 263 | internal_ciphers += ":"; |
| 264 | internal_ciphers += entry->internal_name; |
| 265 | break; |
| 266 | } |
| 267 | } |
| 268 | |
| 269 | if (!found) { |
| 270 | LOG(LS_ERROR) << "Could not find cipher: " << *cipher; |
| 271 | return false; |
| 272 | } |
| 273 | } |
| 274 | |
| 275 | if (internal_ciphers.empty()) |
| 276 | return false; |
| 277 | |
| 278 | srtp_ciphers_ = internal_ciphers; |
| 279 | return true; |
| 280 | #else |
| 281 | return false; |
| 282 | #endif |
| 283 | } |
| 284 | |
| 285 | bool OpenSSLStreamAdapter::GetDtlsSrtpCipher(std::string* cipher) { |
| 286 | #ifdef HAVE_DTLS_SRTP |
| 287 | ASSERT(state_ == SSL_CONNECTED); |
| 288 | if (state_ != SSL_CONNECTED) |
| 289 | return false; |
| 290 | |
| 291 | SRTP_PROTECTION_PROFILE *srtp_profile = |
| 292 | SSL_get_selected_srtp_profile(ssl_); |
| 293 | |
| 294 | if (!srtp_profile) |
| 295 | return false; |
| 296 | |
| 297 | for (SrtpCipherMapEntry *entry = SrtpCipherMap; |
| 298 | entry->internal_name; ++entry) { |
| 299 | if (!strcmp(entry->internal_name, srtp_profile->name)) { |
| 300 | *cipher = entry->external_name; |
| 301 | return true; |
| 302 | } |
| 303 | } |
| 304 | |
| 305 | ASSERT(false); // This should never happen |
| 306 | |
| 307 | return false; |
| 308 | #else |
| 309 | return false; |
| 310 | #endif |
| 311 | } |
| 312 | |
| 313 | int OpenSSLStreamAdapter::StartSSLWithServer(const char* server_name) { |
| 314 | ASSERT(server_name != NULL && server_name[0] != '\0'); |
| 315 | ssl_server_name_ = server_name; |
| 316 | return StartSSL(); |
| 317 | } |
| 318 | |
| 319 | int OpenSSLStreamAdapter::StartSSLWithPeer() { |
| 320 | ASSERT(ssl_server_name_.empty()); |
| 321 | // It is permitted to specify peer_certificate_ only later. |
| 322 | return StartSSL(); |
| 323 | } |
| 324 | |
| 325 | void OpenSSLStreamAdapter::SetMode(SSLMode mode) { |
| 326 | ASSERT(state_ == SSL_NONE); |
| 327 | ssl_mode_ = mode; |
| 328 | } |
| 329 | |
| 330 | // |
| 331 | // StreamInterface Implementation |
| 332 | // |
| 333 | |
| 334 | StreamResult OpenSSLStreamAdapter::Write(const void* data, size_t data_len, |
| 335 | size_t* written, int* error) { |
| 336 | LOG(LS_VERBOSE) << "OpenSSLStreamAdapter::Write(" << data_len << ")"; |
| 337 | |
| 338 | switch (state_) { |
| 339 | case SSL_NONE: |
| 340 | // pass-through in clear text |
| 341 | return StreamAdapterInterface::Write(data, data_len, written, error); |
| 342 | |
| 343 | case SSL_WAIT: |
| 344 | case SSL_CONNECTING: |
| 345 | return SR_BLOCK; |
| 346 | |
| 347 | case SSL_CONNECTED: |
| 348 | break; |
| 349 | |
| 350 | case SSL_ERROR: |
| 351 | case SSL_CLOSED: |
| 352 | default: |
| 353 | if (error) |
| 354 | *error = ssl_error_code_; |
| 355 | return SR_ERROR; |
| 356 | } |
| 357 | |
| 358 | // OpenSSL will return an error if we try to write zero bytes |
| 359 | if (data_len == 0) { |
| 360 | if (written) |
| 361 | *written = 0; |
| 362 | return SR_SUCCESS; |
| 363 | } |
| 364 | |
| 365 | ssl_write_needs_read_ = false; |
| 366 | |
| 367 | int code = SSL_write(ssl_, data, data_len); |
| 368 | int ssl_error = SSL_get_error(ssl_, code); |
| 369 | switch (ssl_error) { |
| 370 | case SSL_ERROR_NONE: |
| 371 | LOG(LS_VERBOSE) << " -- success"; |
| 372 | ASSERT(0 < code && static_cast<unsigned>(code) <= data_len); |
| 373 | if (written) |
| 374 | *written = code; |
| 375 | return SR_SUCCESS; |
| 376 | case SSL_ERROR_WANT_READ: |
| 377 | LOG(LS_VERBOSE) << " -- error want read"; |
| 378 | ssl_write_needs_read_ = true; |
| 379 | return SR_BLOCK; |
| 380 | case SSL_ERROR_WANT_WRITE: |
| 381 | LOG(LS_VERBOSE) << " -- error want write"; |
| 382 | return SR_BLOCK; |
| 383 | |
| 384 | case SSL_ERROR_ZERO_RETURN: |
| 385 | default: |
| 386 | Error("SSL_write", (ssl_error ? ssl_error : -1), false); |
| 387 | if (error) |
| 388 | *error = ssl_error_code_; |
| 389 | return SR_ERROR; |
| 390 | } |
| 391 | // not reached |
| 392 | } |
| 393 | |
| 394 | StreamResult OpenSSLStreamAdapter::Read(void* data, size_t data_len, |
| 395 | size_t* read, int* error) { |
| 396 | LOG(LS_VERBOSE) << "OpenSSLStreamAdapter::Read(" << data_len << ")"; |
| 397 | switch (state_) { |
| 398 | case SSL_NONE: |
| 399 | // pass-through in clear text |
| 400 | return StreamAdapterInterface::Read(data, data_len, read, error); |
| 401 | |
| 402 | case SSL_WAIT: |
| 403 | case SSL_CONNECTING: |
| 404 | return SR_BLOCK; |
| 405 | |
| 406 | case SSL_CONNECTED: |
| 407 | break; |
| 408 | |
| 409 | case SSL_CLOSED: |
| 410 | return SR_EOS; |
| 411 | |
| 412 | case SSL_ERROR: |
| 413 | default: |
| 414 | if (error) |
| 415 | *error = ssl_error_code_; |
| 416 | return SR_ERROR; |
| 417 | } |
| 418 | |
| 419 | // Don't trust OpenSSL with zero byte reads |
| 420 | if (data_len == 0) { |
| 421 | if (read) |
| 422 | *read = 0; |
| 423 | return SR_SUCCESS; |
| 424 | } |
| 425 | |
| 426 | ssl_read_needs_write_ = false; |
| 427 | |
| 428 | int code = SSL_read(ssl_, data, data_len); |
| 429 | int ssl_error = SSL_get_error(ssl_, code); |
| 430 | switch (ssl_error) { |
| 431 | case SSL_ERROR_NONE: |
| 432 | LOG(LS_VERBOSE) << " -- success"; |
| 433 | ASSERT(0 < code && static_cast<unsigned>(code) <= data_len); |
| 434 | if (read) |
| 435 | *read = code; |
| 436 | |
| 437 | if (ssl_mode_ == SSL_MODE_DTLS) { |
| 438 | // Enforce atomic reads -- this is a short read |
| 439 | unsigned int pending = SSL_pending(ssl_); |
| 440 | |
| 441 | if (pending) { |
| 442 | LOG(LS_INFO) << " -- short DTLS read. flushing"; |
| 443 | FlushInput(pending); |
| 444 | if (error) |
| 445 | *error = SSE_MSG_TRUNC; |
| 446 | return SR_ERROR; |
| 447 | } |
| 448 | } |
| 449 | return SR_SUCCESS; |
| 450 | case SSL_ERROR_WANT_READ: |
| 451 | LOG(LS_VERBOSE) << " -- error want read"; |
| 452 | return SR_BLOCK; |
| 453 | case SSL_ERROR_WANT_WRITE: |
| 454 | LOG(LS_VERBOSE) << " -- error want write"; |
| 455 | ssl_read_needs_write_ = true; |
| 456 | return SR_BLOCK; |
| 457 | case SSL_ERROR_ZERO_RETURN: |
| 458 | LOG(LS_VERBOSE) << " -- remote side closed"; |
| 459 | return SR_EOS; |
| 460 | break; |
| 461 | default: |
| 462 | LOG(LS_VERBOSE) << " -- error " << code; |
| 463 | Error("SSL_read", (ssl_error ? ssl_error : -1), false); |
| 464 | if (error) |
| 465 | *error = ssl_error_code_; |
| 466 | return SR_ERROR; |
| 467 | } |
| 468 | // not reached |
| 469 | } |
| 470 | |
| 471 | void OpenSSLStreamAdapter::FlushInput(unsigned int left) { |
| 472 | unsigned char buf[2048]; |
| 473 | |
| 474 | while (left) { |
| 475 | // This should always succeed |
| 476 | int toread = (sizeof(buf) < left) ? sizeof(buf) : left; |
| 477 | int code = SSL_read(ssl_, buf, toread); |
| 478 | |
| 479 | int ssl_error = SSL_get_error(ssl_, code); |
| 480 | ASSERT(ssl_error == SSL_ERROR_NONE); |
| 481 | |
| 482 | if (ssl_error != SSL_ERROR_NONE) { |
| 483 | LOG(LS_VERBOSE) << " -- error " << code; |
| 484 | Error("SSL_read", (ssl_error ? ssl_error : -1), false); |
| 485 | return; |
| 486 | } |
| 487 | |
| 488 | LOG(LS_VERBOSE) << " -- flushed " << code << " bytes"; |
| 489 | left -= code; |
| 490 | } |
| 491 | } |
| 492 | |
| 493 | void OpenSSLStreamAdapter::Close() { |
| 494 | Cleanup(); |
| 495 | ASSERT(state_ == SSL_CLOSED || state_ == SSL_ERROR); |
| 496 | StreamAdapterInterface::Close(); |
| 497 | } |
| 498 | |
| 499 | StreamState OpenSSLStreamAdapter::GetState() const { |
| 500 | switch (state_) { |
| 501 | case SSL_WAIT: |
| 502 | case SSL_CONNECTING: |
| 503 | return SS_OPENING; |
| 504 | case SSL_CONNECTED: |
| 505 | return SS_OPEN; |
| 506 | default: |
| 507 | return SS_CLOSED; |
| 508 | }; |
| 509 | // not reached |
| 510 | } |
| 511 | |
| 512 | void OpenSSLStreamAdapter::OnEvent(StreamInterface* stream, int events, |
| 513 | int err) { |
| 514 | int events_to_signal = 0; |
| 515 | int signal_error = 0; |
| 516 | ASSERT(stream == this->stream()); |
| 517 | if ((events & SE_OPEN)) { |
| 518 | LOG(LS_VERBOSE) << "OpenSSLStreamAdapter::OnEvent SE_OPEN"; |
| 519 | if (state_ != SSL_WAIT) { |
| 520 | ASSERT(state_ == SSL_NONE); |
| 521 | events_to_signal |= SE_OPEN; |
| 522 | } else { |
| 523 | state_ = SSL_CONNECTING; |
| 524 | if (int err = BeginSSL()) { |
| 525 | Error("BeginSSL", err, true); |
| 526 | return; |
| 527 | } |
| 528 | } |
| 529 | } |
| 530 | if ((events & (SE_READ|SE_WRITE))) { |
| 531 | LOG(LS_VERBOSE) << "OpenSSLStreamAdapter::OnEvent" |
| 532 | << ((events & SE_READ) ? " SE_READ" : "") |
| 533 | << ((events & SE_WRITE) ? " SE_WRITE" : ""); |
| 534 | if (state_ == SSL_NONE) { |
| 535 | events_to_signal |= events & (SE_READ|SE_WRITE); |
| 536 | } else if (state_ == SSL_CONNECTING) { |
| 537 | if (int err = ContinueSSL()) { |
| 538 | Error("ContinueSSL", err, true); |
| 539 | return; |
| 540 | } |
| 541 | } else if (state_ == SSL_CONNECTED) { |
| 542 | if (((events & SE_READ) && ssl_write_needs_read_) || |
| 543 | (events & SE_WRITE)) { |
| 544 | LOG(LS_VERBOSE) << " -- onStreamWriteable"; |
| 545 | events_to_signal |= SE_WRITE; |
| 546 | } |
| 547 | if (((events & SE_WRITE) && ssl_read_needs_write_) || |
| 548 | (events & SE_READ)) { |
| 549 | LOG(LS_VERBOSE) << " -- onStreamReadable"; |
| 550 | events_to_signal |= SE_READ; |
| 551 | } |
| 552 | } |
| 553 | } |
| 554 | if ((events & SE_CLOSE)) { |
| 555 | LOG(LS_VERBOSE) << "OpenSSLStreamAdapter::OnEvent(SE_CLOSE, " << err << ")"; |
| 556 | Cleanup(); |
| 557 | events_to_signal |= SE_CLOSE; |
| 558 | // SE_CLOSE is the only event that uses the final parameter to OnEvent(). |
| 559 | ASSERT(signal_error == 0); |
| 560 | signal_error = err; |
| 561 | } |
| 562 | if (events_to_signal) |
| 563 | StreamAdapterInterface::OnEvent(stream, events_to_signal, signal_error); |
| 564 | } |
| 565 | |
| 566 | int OpenSSLStreamAdapter::StartSSL() { |
| 567 | ASSERT(state_ == SSL_NONE); |
| 568 | |
| 569 | if (StreamAdapterInterface::GetState() != SS_OPEN) { |
| 570 | state_ = SSL_WAIT; |
| 571 | return 0; |
| 572 | } |
| 573 | |
| 574 | state_ = SSL_CONNECTING; |
| 575 | if (int err = BeginSSL()) { |
| 576 | Error("BeginSSL", err, false); |
| 577 | return err; |
| 578 | } |
| 579 | |
| 580 | return 0; |
| 581 | } |
| 582 | |
| 583 | int OpenSSLStreamAdapter::BeginSSL() { |
| 584 | ASSERT(state_ == SSL_CONNECTING); |
| 585 | // The underlying stream has open. If we are in peer-to-peer mode |
| 586 | // then a peer certificate must have been specified by now. |
| 587 | ASSERT(!ssl_server_name_.empty() || |
| 588 | !peer_certificate_digest_algorithm_.empty()); |
| 589 | LOG(LS_INFO) << "BeginSSL: " |
| 590 | << (!ssl_server_name_.empty() ? ssl_server_name_ : |
| 591 | "with peer"); |
| 592 | |
| 593 | BIO* bio = NULL; |
| 594 | |
| 595 | // First set up the context |
| 596 | ASSERT(ssl_ctx_ == NULL); |
| 597 | ssl_ctx_ = SetupSSLContext(); |
| 598 | if (!ssl_ctx_) |
| 599 | return -1; |
| 600 | |
| 601 | bio = BIO_new_stream(static_cast<StreamInterface*>(stream())); |
| 602 | if (!bio) |
| 603 | return -1; |
| 604 | |
| 605 | ssl_ = SSL_new(ssl_ctx_); |
| 606 | if (!ssl_) { |
| 607 | BIO_free(bio); |
| 608 | return -1; |
| 609 | } |
| 610 | |
| 611 | SSL_set_app_data(ssl_, this); |
| 612 | |
| 613 | SSL_set_bio(ssl_, bio, bio); // the SSL object owns the bio now. |
| 614 | |
| 615 | SSL_set_mode(ssl_, SSL_MODE_ENABLE_PARTIAL_WRITE | |
| 616 | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER); |
| 617 | |
| 618 | // Do the connect |
| 619 | return ContinueSSL(); |
| 620 | } |
| 621 | |
| 622 | int OpenSSLStreamAdapter::ContinueSSL() { |
| 623 | LOG(LS_VERBOSE) << "ContinueSSL"; |
| 624 | ASSERT(state_ == SSL_CONNECTING); |
| 625 | |
| 626 | // Clear the DTLS timer |
| 627 | Thread::Current()->Clear(this, MSG_TIMEOUT); |
| 628 | |
| 629 | int code = (role_ == SSL_CLIENT) ? SSL_connect(ssl_) : SSL_accept(ssl_); |
| 630 | int ssl_error; |
| 631 | switch (ssl_error = SSL_get_error(ssl_, code)) { |
| 632 | case SSL_ERROR_NONE: |
| 633 | LOG(LS_VERBOSE) << " -- success"; |
| 634 | |
| 635 | if (!SSLPostConnectionCheck(ssl_, ssl_server_name_.c_str(), NULL, |
| 636 | peer_certificate_digest_algorithm_)) { |
| 637 | LOG(LS_ERROR) << "TLS post connection check failed"; |
| 638 | return -1; |
| 639 | } |
| 640 | |
| 641 | state_ = SSL_CONNECTED; |
| 642 | StreamAdapterInterface::OnEvent(stream(), SE_OPEN|SE_READ|SE_WRITE, 0); |
| 643 | break; |
| 644 | |
| 645 | case SSL_ERROR_WANT_READ: { |
| 646 | LOG(LS_VERBOSE) << " -- error want read"; |
| 647 | struct timeval timeout; |
| 648 | if (DTLSv1_get_timeout(ssl_, &timeout)) { |
| 649 | int delay = timeout.tv_sec * 1000 + timeout.tv_usec/1000; |
| 650 | |
| 651 | Thread::Current()->PostDelayed(delay, this, MSG_TIMEOUT, 0); |
| 652 | } |
| 653 | } |
| 654 | break; |
| 655 | |
| 656 | case SSL_ERROR_WANT_WRITE: |
| 657 | LOG(LS_VERBOSE) << " -- error want write"; |
| 658 | break; |
| 659 | |
| 660 | case SSL_ERROR_ZERO_RETURN: |
| 661 | default: |
| 662 | LOG(LS_VERBOSE) << " -- error " << code; |
| 663 | return (ssl_error != 0) ? ssl_error : -1; |
| 664 | } |
| 665 | |
| 666 | return 0; |
| 667 | } |
| 668 | |
| 669 | void OpenSSLStreamAdapter::Error(const char* context, int err, bool signal) { |
| 670 | LOG(LS_WARNING) << "OpenSSLStreamAdapter::Error(" |
| 671 | << context << ", " << err << ")"; |
| 672 | state_ = SSL_ERROR; |
| 673 | ssl_error_code_ = err; |
| 674 | Cleanup(); |
| 675 | if (signal) |
| 676 | StreamAdapterInterface::OnEvent(stream(), SE_CLOSE, err); |
| 677 | } |
| 678 | |
| 679 | void OpenSSLStreamAdapter::Cleanup() { |
| 680 | LOG(LS_INFO) << "Cleanup"; |
| 681 | |
| 682 | if (state_ != SSL_ERROR) { |
| 683 | state_ = SSL_CLOSED; |
| 684 | ssl_error_code_ = 0; |
| 685 | } |
| 686 | |
| 687 | if (ssl_) { |
| 688 | SSL_free(ssl_); |
| 689 | ssl_ = NULL; |
| 690 | } |
| 691 | if (ssl_ctx_) { |
| 692 | SSL_CTX_free(ssl_ctx_); |
| 693 | ssl_ctx_ = NULL; |
| 694 | } |
| 695 | identity_.reset(); |
| 696 | peer_certificate_.reset(); |
| 697 | |
| 698 | // Clear the DTLS timer |
| 699 | Thread::Current()->Clear(this, MSG_TIMEOUT); |
| 700 | } |
| 701 | |
| 702 | |
| 703 | void OpenSSLStreamAdapter::OnMessage(Message* msg) { |
| 704 | // Process our own messages and then pass others to the superclass |
| 705 | if (MSG_TIMEOUT == msg->message_id) { |
| 706 | LOG(LS_INFO) << "DTLS timeout expired"; |
| 707 | DTLSv1_handle_timeout(ssl_); |
| 708 | ContinueSSL(); |
| 709 | } else { |
| 710 | StreamInterface::OnMessage(msg); |
| 711 | } |
| 712 | } |
| 713 | |
| 714 | SSL_CTX* OpenSSLStreamAdapter::SetupSSLContext() { |
| 715 | SSL_CTX *ctx = NULL; |
| 716 | |
| 717 | if (role_ == SSL_CLIENT) { |
| 718 | ctx = SSL_CTX_new(ssl_mode_ == SSL_MODE_DTLS ? |
| 719 | DTLSv1_client_method() : TLSv1_client_method()); |
| 720 | } else { |
| 721 | ctx = SSL_CTX_new(ssl_mode_ == SSL_MODE_DTLS ? |
| 722 | DTLSv1_server_method() : TLSv1_server_method()); |
| 723 | } |
| 724 | if (ctx == NULL) |
| 725 | return NULL; |
| 726 | |
| 727 | if (identity_ && !identity_->ConfigureIdentity(ctx)) { |
| 728 | SSL_CTX_free(ctx); |
| 729 | return NULL; |
| 730 | } |
| 731 | |
| 732 | #ifdef _DEBUG |
| 733 | SSL_CTX_set_info_callback(ctx, OpenSSLAdapter::SSLInfoCallback); |
| 734 | #endif |
| 735 | |
| 736 | SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER |SSL_VERIFY_FAIL_IF_NO_PEER_CERT, |
| 737 | SSLVerifyCallback); |
| 738 | SSL_CTX_set_verify_depth(ctx, 4); |
| 739 | SSL_CTX_set_cipher_list(ctx, "ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH"); |
| 740 | |
| 741 | #ifdef HAVE_DTLS_SRTP |
| 742 | if (!srtp_ciphers_.empty()) { |
| 743 | if (SSL_CTX_set_tlsext_use_srtp(ctx, srtp_ciphers_.c_str())) { |
| 744 | SSL_CTX_free(ctx); |
| 745 | return NULL; |
| 746 | } |
| 747 | } |
| 748 | #endif |
| 749 | |
| 750 | return ctx; |
| 751 | } |
| 752 | |
| 753 | int OpenSSLStreamAdapter::SSLVerifyCallback(int ok, X509_STORE_CTX* store) { |
| 754 | // Get our SSL structure from the store |
| 755 | SSL* ssl = reinterpret_cast<SSL*>(X509_STORE_CTX_get_ex_data( |
| 756 | store, |
| 757 | SSL_get_ex_data_X509_STORE_CTX_idx())); |
| 758 | OpenSSLStreamAdapter* stream = |
| 759 | reinterpret_cast<OpenSSLStreamAdapter*>(SSL_get_app_data(ssl)); |
| 760 | |
| 761 | if (stream->peer_certificate_digest_algorithm_.empty()) { |
| 762 | return 0; |
| 763 | } |
| 764 | X509* cert = X509_STORE_CTX_get_current_cert(store); |
| 765 | unsigned char digest[EVP_MAX_MD_SIZE]; |
| 766 | size_t digest_length; |
| 767 | if (!OpenSSLCertificate::ComputeDigest( |
| 768 | cert, |
| 769 | stream->peer_certificate_digest_algorithm_, |
| 770 | digest, sizeof(digest), |
| 771 | &digest_length)) { |
| 772 | LOG(LS_WARNING) << "Failed to compute peer cert digest."; |
| 773 | return 0; |
| 774 | } |
| 775 | Buffer computed_digest(digest, digest_length); |
| 776 | if (computed_digest != stream->peer_certificate_digest_value_) { |
| 777 | LOG(LS_WARNING) << "Rejected peer certificate due to mismatched digest."; |
| 778 | return 0; |
| 779 | } |
| 780 | // Ignore any verification error if the digest matches, since there is no |
| 781 | // value in checking the validity of a self-signed cert issued by untrusted |
| 782 | // sources. |
| 783 | LOG(LS_INFO) << "Accepted peer certificate."; |
| 784 | // Record the peer's certificate. |
| 785 | stream->peer_certificate_.reset(new OpenSSLCertificate(cert)); |
| 786 | return 1; |
| 787 | } |
| 788 | |
| 789 | // This code is taken from the "Network Security with OpenSSL" |
| 790 | // sample in chapter 5 |
| 791 | bool OpenSSLStreamAdapter::SSLPostConnectionCheck(SSL* ssl, |
| 792 | const char* server_name, |
| 793 | const X509* peer_cert, |
| 794 | const std::string |
| 795 | &peer_digest) { |
| 796 | ASSERT(server_name != NULL); |
| 797 | bool ok; |
| 798 | if (server_name[0] != '\0') { // traditional mode |
| 799 | ok = OpenSSLAdapter::VerifyServerName(ssl, server_name, ignore_bad_cert()); |
| 800 | |
| 801 | if (ok) { |
| 802 | ok = (SSL_get_verify_result(ssl) == X509_V_OK || |
| 803 | custom_verification_succeeded_); |
| 804 | } |
| 805 | } else { // peer-to-peer mode |
| 806 | ASSERT((peer_cert != NULL) || (!peer_digest.empty())); |
| 807 | // no server name validation |
| 808 | ok = true; |
| 809 | } |
| 810 | |
| 811 | if (!ok && ignore_bad_cert()) { |
| 812 | LOG(LS_ERROR) << "SSL_get_verify_result(ssl) = " |
| 813 | << SSL_get_verify_result(ssl); |
| 814 | LOG(LS_INFO) << "Other TLS post connection checks failed."; |
| 815 | ok = true; |
| 816 | } |
| 817 | |
| 818 | return ok; |
| 819 | } |
| 820 | |
| 821 | bool OpenSSLStreamAdapter::HaveDtls() { |
| 822 | return true; |
| 823 | } |
| 824 | |
| 825 | bool OpenSSLStreamAdapter::HaveDtlsSrtp() { |
| 826 | #ifdef HAVE_DTLS_SRTP |
| 827 | return true; |
| 828 | #else |
| 829 | return false; |
| 830 | #endif |
| 831 | } |
| 832 | |
| 833 | bool OpenSSLStreamAdapter::HaveExporter() { |
| 834 | #ifdef HAVE_DTLS_SRTP |
| 835 | return true; |
| 836 | #else |
| 837 | return false; |
| 838 | #endif |
| 839 | } |
| 840 | |
| 841 | } // namespace rtc |
| 842 | |
| 843 | #endif // HAVE_OPENSSL_SSL_H |