1 // 2 // Copyright (C) 2009 The Android Open Source Project 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 // 16 17 #include "update_engine/libcurl_http_fetcher.h" 18 19 #include <sys/types.h> 20 #include <unistd.h> 21 22 #include <algorithm> 23 #include <string> 24 25 #include <base/bind.h> 26 #include <base/format_macros.h> 27 #include <base/location.h> 28 #include <base/logging.h> 29 #include <base/strings/string_util.h> 30 #include <base/strings/stringprintf.h> 31 32 #ifdef __ANDROID__ 33 #include <cutils/qtaguid.h> 34 #include <private/android_filesystem_config.h> 35 #endif // __ANDROID__ 36 37 #include "update_engine/certificate_checker.h" 38 #include "update_engine/common/hardware_interface.h" 39 #include "update_engine/common/platform_constants.h" 40 41 using base::TimeDelta; 42 using brillo::MessageLoop; 43 using std::max; 44 using std::string; 45 46 // This is a concrete implementation of HttpFetcher that uses libcurl to do the 47 // http work. 48 49 namespace chromeos_update_engine { 50 51 namespace { 52 53 const int kNoNetworkRetrySeconds = 10; 54 55 // libcurl's CURLOPT_SOCKOPTFUNCTION callback function. Called after the socket 56 // is created but before it is connected. This callback tags the created socket 57 // so the network usage can be tracked in Android. 58 int LibcurlSockoptCallback(void* /* clientp */, 59 curl_socket_t curlfd, 60 curlsocktype /* purpose */) { 61 #ifdef __ANDROID__ 62 // Socket tag used by all network sockets. See qtaguid kernel module for 63 // stats. 64 const int kUpdateEngineSocketTag = 0x55417243; // "CrAU" in little-endian. 65 qtaguid_tagSocket(curlfd, kUpdateEngineSocketTag, AID_OTA_UPDATE); 66 #endif // __ANDROID__ 67 return CURL_SOCKOPT_OK; 68 } 69 70 } // namespace 71 72 // static 73 int LibcurlHttpFetcher::LibcurlCloseSocketCallback(void* clientp, 74 curl_socket_t item) { 75 #ifdef __ANDROID__ 76 qtaguid_untagSocket(item); 77 #endif // __ANDROID__ 78 LibcurlHttpFetcher* fetcher = static_cast<LibcurlHttpFetcher*>(clientp); 79 // Stop watching the socket before closing it. 80 for (size_t t = 0; t < arraysize(fetcher->fd_task_maps_); ++t) { 81 const auto fd_task_pair = fetcher->fd_task_maps_[t].find(item); 82 if (fd_task_pair != fetcher->fd_task_maps_[t].end()) { 83 if (!MessageLoop::current()->CancelTask(fd_task_pair->second)) { 84 LOG(WARNING) << "Error canceling the watch task " 85 << fd_task_pair->second << " for " 86 << (t ? "writing" : "reading") << " the fd " << item; 87 } 88 fetcher->fd_task_maps_[t].erase(item); 89 } 90 } 91 92 // Documentation for this callback says to return 0 on success or 1 on error. 93 if (!IGNORE_EINTR(close(item))) 94 return 0; 95 return 1; 96 } 97 98 LibcurlHttpFetcher::LibcurlHttpFetcher(ProxyResolver* proxy_resolver, 99 HardwareInterface* hardware) 100 : HttpFetcher(proxy_resolver), hardware_(hardware) { 101 // Dev users want a longer timeout (180 seconds) because they may 102 // be waiting on the dev server to build an image. 103 if (!hardware_->IsOfficialBuild()) 104 low_speed_time_seconds_ = kDownloadDevModeLowSpeedTimeSeconds; 105 if (hardware_->IsOOBEEnabled() && !hardware_->IsOOBEComplete(nullptr)) 106 max_retry_count_ = kDownloadMaxRetryCountOobeNotComplete; 107 } 108 109 LibcurlHttpFetcher::~LibcurlHttpFetcher() { 110 LOG_IF(ERROR, transfer_in_progress_) 111 << "Destroying the fetcher while a transfer is in progress."; 112 CancelProxyResolution(); 113 CleanUp(); 114 } 115 116 bool LibcurlHttpFetcher::GetProxyType(const string& proxy, 117 curl_proxytype* out_type) { 118 if (base::StartsWith( 119 proxy, "socks5://", base::CompareCase::INSENSITIVE_ASCII) || 120 base::StartsWith( 121 proxy, "socks://", base::CompareCase::INSENSITIVE_ASCII)) { 122 *out_type = CURLPROXY_SOCKS5_HOSTNAME; 123 return true; 124 } 125 if (base::StartsWith( 126 proxy, "socks4://", base::CompareCase::INSENSITIVE_ASCII)) { 127 *out_type = CURLPROXY_SOCKS4A; 128 return true; 129 } 130 if (base::StartsWith( 131 proxy, "http://", base::CompareCase::INSENSITIVE_ASCII) || 132 base::StartsWith( 133 proxy, "https://", base::CompareCase::INSENSITIVE_ASCII)) { 134 *out_type = CURLPROXY_HTTP; 135 return true; 136 } 137 if (base::StartsWith(proxy, kNoProxy, base::CompareCase::INSENSITIVE_ASCII)) { 138 // known failure case. don't log. 139 return false; 140 } 141 LOG(INFO) << "Unknown proxy type: " << proxy; 142 return false; 143 } 144 145 void LibcurlHttpFetcher::ResumeTransfer(const string& url) { 146 LOG(INFO) << "Starting/Resuming transfer"; 147 CHECK(!transfer_in_progress_); 148 url_ = url; 149 curl_multi_handle_ = curl_multi_init(); 150 CHECK(curl_multi_handle_); 151 152 curl_handle_ = curl_easy_init(); 153 CHECK(curl_handle_); 154 ignore_failure_ = false; 155 156 // Tag and untag the socket for network usage stats. 157 curl_easy_setopt( 158 curl_handle_, CURLOPT_SOCKOPTFUNCTION, LibcurlSockoptCallback); 159 curl_easy_setopt( 160 curl_handle_, CURLOPT_CLOSESOCKETFUNCTION, LibcurlCloseSocketCallback); 161 curl_easy_setopt(curl_handle_, CURLOPT_CLOSESOCKETDATA, this); 162 163 CHECK(HasProxy()); 164 bool is_direct = (GetCurrentProxy() == kNoProxy); 165 LOG(INFO) << "Using proxy: " << (is_direct ? "no" : "yes"); 166 if (is_direct) { 167 CHECK_EQ(curl_easy_setopt(curl_handle_, 168 CURLOPT_PROXY, 169 ""), CURLE_OK); 170 } else { 171 CHECK_EQ(curl_easy_setopt(curl_handle_, 172 CURLOPT_PROXY, 173 GetCurrentProxy().c_str()), CURLE_OK); 174 // Curl seems to require us to set the protocol 175 curl_proxytype type; 176 if (GetProxyType(GetCurrentProxy(), &type)) { 177 CHECK_EQ(curl_easy_setopt(curl_handle_, 178 CURLOPT_PROXYTYPE, 179 type), CURLE_OK); 180 } 181 } 182 183 if (post_data_set_) { 184 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_POST, 1), CURLE_OK); 185 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_POSTFIELDS, 186 post_data_.data()), 187 CURLE_OK); 188 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_POSTFIELDSIZE, 189 post_data_.size()), 190 CURLE_OK); 191 } 192 193 // Setup extra HTTP headers. 194 if (curl_http_headers_) { 195 curl_slist_free_all(curl_http_headers_); 196 curl_http_headers_ = nullptr; 197 } 198 for (const auto& header : extra_headers_) { 199 // curl_slist_append() copies the string. 200 curl_http_headers_ = 201 curl_slist_append(curl_http_headers_, header.second.c_str()); 202 } 203 if (post_data_set_) { 204 // Set the Content-Type HTTP header, if one was specifically set. 205 if (post_content_type_ != kHttpContentTypeUnspecified) { 206 const string content_type_attr = base::StringPrintf( 207 "Content-Type: %s", GetHttpContentTypeString(post_content_type_)); 208 curl_http_headers_ = 209 curl_slist_append(curl_http_headers_, content_type_attr.c_str()); 210 } else { 211 LOG(WARNING) << "no content type set, using libcurl default"; 212 } 213 } 214 CHECK_EQ( 215 curl_easy_setopt(curl_handle_, CURLOPT_HTTPHEADER, curl_http_headers_), 216 CURLE_OK); 217 218 if (bytes_downloaded_ > 0 || download_length_) { 219 // Resume from where we left off. 220 resume_offset_ = bytes_downloaded_; 221 CHECK_GE(resume_offset_, 0); 222 223 // Compute end offset, if one is specified. As per HTTP specification, this 224 // is an inclusive boundary. Make sure it doesn't overflow. 225 size_t end_offset = 0; 226 if (download_length_) { 227 end_offset = static_cast<size_t>(resume_offset_) + download_length_ - 1; 228 CHECK_LE((size_t) resume_offset_, end_offset); 229 } 230 231 // Create a string representation of the desired range. 232 string range_str = base::StringPrintf( 233 "%" PRIu64 "-", static_cast<uint64_t>(resume_offset_)); 234 if (end_offset) 235 range_str += std::to_string(end_offset); 236 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_RANGE, range_str.c_str()), 237 CURLE_OK); 238 } 239 240 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_WRITEDATA, this), CURLE_OK); 241 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_WRITEFUNCTION, 242 StaticLibcurlWrite), CURLE_OK); 243 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_URL, url_.c_str()), 244 CURLE_OK); 245 246 // If the connection drops under |low_speed_limit_bps_| (10 247 // bytes/sec by default) for |low_speed_time_seconds_| (90 seconds, 248 // 180 on non-official builds), reconnect. 249 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_LOW_SPEED_LIMIT, 250 low_speed_limit_bps_), 251 CURLE_OK); 252 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_LOW_SPEED_TIME, 253 low_speed_time_seconds_), 254 CURLE_OK); 255 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_CONNECTTIMEOUT, 256 connect_timeout_seconds_), 257 CURLE_OK); 258 259 // By default, libcurl doesn't follow redirections. Allow up to 260 // |kDownloadMaxRedirects| redirections. 261 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_FOLLOWLOCATION, 1), CURLE_OK); 262 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_MAXREDIRS, 263 kDownloadMaxRedirects), 264 CURLE_OK); 265 266 // Lock down the appropriate curl options for HTTP or HTTPS depending on 267 // the url. 268 if (hardware_->IsOfficialBuild()) { 269 if (base::StartsWith( 270 url_, "http://", base::CompareCase::INSENSITIVE_ASCII)) { 271 SetCurlOptionsForHttp(); 272 } else if (base::StartsWith( 273 url_, "https://", base::CompareCase::INSENSITIVE_ASCII)) { 274 SetCurlOptionsForHttps(); 275 #if !USE_OMAHA 276 } else if (base::StartsWith( 277 url_, "file://", base::CompareCase::INSENSITIVE_ASCII)) { 278 SetCurlOptionsForFile(); 279 #endif 280 } else { 281 LOG(ERROR) << "Received invalid URI: " << url_; 282 // Lock down to no protocol supported for the transfer. 283 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROTOCOLS, 0), CURLE_OK); 284 } 285 } else { 286 LOG(INFO) << "Not setting http(s) curl options because we are " 287 << "running a dev/test image"; 288 } 289 290 CHECK_EQ(curl_multi_add_handle(curl_multi_handle_, curl_handle_), CURLM_OK); 291 transfer_in_progress_ = true; 292 } 293 294 // Lock down only the protocol in case of HTTP. 295 void LibcurlHttpFetcher::SetCurlOptionsForHttp() { 296 LOG(INFO) << "Setting up curl options for HTTP"; 297 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROTOCOLS, CURLPROTO_HTTP), 298 CURLE_OK); 299 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_REDIR_PROTOCOLS, 300 CURLPROTO_HTTP), 301 CURLE_OK); 302 } 303 304 // Security lock-down in official builds: makes sure that peer certificate 305 // verification is enabled, restricts the set of trusted certificates, 306 // restricts protocols to HTTPS, restricts ciphers to HIGH. 307 void LibcurlHttpFetcher::SetCurlOptionsForHttps() { 308 LOG(INFO) << "Setting up curl options for HTTPS"; 309 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_VERIFYPEER, 1), 310 CURLE_OK); 311 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_VERIFYHOST, 2), 312 CURLE_OK); 313 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_CAPATH, 314 constants::kCACertificatesPath), 315 CURLE_OK); 316 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROTOCOLS, CURLPROTO_HTTPS), 317 CURLE_OK); 318 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_REDIR_PROTOCOLS, 319 CURLPROTO_HTTPS), 320 CURLE_OK); 321 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_CIPHER_LIST, "HIGH:!ADH"), 322 CURLE_OK); 323 if (server_to_check_ != ServerToCheck::kNone) { 324 CHECK_EQ( 325 curl_easy_setopt(curl_handle_, CURLOPT_SSL_CTX_DATA, &server_to_check_), 326 CURLE_OK); 327 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_CTX_FUNCTION, 328 CertificateChecker::ProcessSSLContext), 329 CURLE_OK); 330 } 331 } 332 333 // Lock down only the protocol in case of a local file. 334 void LibcurlHttpFetcher::SetCurlOptionsForFile() { 335 LOG(INFO) << "Setting up curl options for FILE"; 336 CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROTOCOLS, CURLPROTO_FILE), 337 CURLE_OK); 338 CHECK_EQ( 339 curl_easy_setopt(curl_handle_, CURLOPT_REDIR_PROTOCOLS, CURLPROTO_FILE), 340 CURLE_OK); 341 } 342 343 // Begins the transfer, which must not have already been started. 344 void LibcurlHttpFetcher::BeginTransfer(const string& url) { 345 CHECK(!transfer_in_progress_); 346 url_ = url; 347 auto closure = base::Bind(&LibcurlHttpFetcher::ProxiesResolved, 348 base::Unretained(this)); 349 ResolveProxiesForUrl(url_, closure); 350 } 351 352 void LibcurlHttpFetcher::ProxiesResolved() { 353 transfer_size_ = -1; 354 resume_offset_ = 0; 355 retry_count_ = 0; 356 no_network_retry_count_ = 0; 357 http_response_code_ = 0; 358 terminate_requested_ = false; 359 sent_byte_ = false; 360 361 // If we are paused, we delay these two operations until Unpause is called. 362 if (transfer_paused_) { 363 restart_transfer_on_unpause_ = true; 364 return; 365 } 366 ResumeTransfer(url_); 367 CurlPerformOnce(); 368 } 369 370 void LibcurlHttpFetcher::ForceTransferTermination() { 371 CancelProxyResolution(); 372 CleanUp(); 373 if (delegate_) { 374 // Note that after the callback returns this object may be destroyed. 375 delegate_->TransferTerminated(this); 376 } 377 } 378 379 void LibcurlHttpFetcher::TerminateTransfer() { 380 if (in_write_callback_) { 381 terminate_requested_ = true; 382 } else { 383 ForceTransferTermination(); 384 } 385 } 386 387 void LibcurlHttpFetcher::SetHeader(const string& header_name, 388 const string& header_value) { 389 string header_line = header_name + ": " + header_value; 390 // Avoid the space if no data on the right side of the semicolon. 391 if (header_value.empty()) 392 header_line = header_name + ":"; 393 TEST_AND_RETURN(header_line.find('\n') == string::npos); 394 TEST_AND_RETURN(header_name.find(':') == string::npos); 395 extra_headers_[base::ToLowerASCII(header_name)] = header_line; 396 } 397 398 void LibcurlHttpFetcher::CurlPerformOnce() { 399 CHECK(transfer_in_progress_); 400 int running_handles = 0; 401 CURLMcode retcode = CURLM_CALL_MULTI_PERFORM; 402 403 // libcurl may request that we immediately call curl_multi_perform after it 404 // returns, so we do. libcurl promises that curl_multi_perform will not block. 405 while (CURLM_CALL_MULTI_PERFORM == retcode) { 406 retcode = curl_multi_perform(curl_multi_handle_, &running_handles); 407 if (terminate_requested_) { 408 ForceTransferTermination(); 409 return; 410 } 411 } 412 413 // If the transfer completes while paused, we should ignore the failure once 414 // the fetcher is unpaused. 415 if (running_handles == 0 && transfer_paused_ && !ignore_failure_) { 416 LOG(INFO) << "Connection closed while paused, ignoring failure."; 417 ignore_failure_ = true; 418 } 419 420 if (running_handles != 0 || transfer_paused_) { 421 // There's either more work to do or we are paused, so we just keep the 422 // file descriptors to watch up to date and exit, until we are done with the 423 // work and we are not paused. 424 SetupMessageLoopSources(); 425 return; 426 } 427 428 // At this point, the transfer was completed in some way (error, connection 429 // closed or download finished). 430 431 GetHttpResponseCode(); 432 if (http_response_code_) { 433 LOG(INFO) << "HTTP response code: " << http_response_code_; 434 no_network_retry_count_ = 0; 435 } else { 436 LOG(ERROR) << "Unable to get http response code."; 437 } 438 439 // we're done! 440 CleanUp(); 441 442 // TODO(petkov): This temporary code tries to deal with the case where the 443 // update engine performs an update check while the network is not ready 444 // (e.g., right after resume). Longer term, we should check if the network 445 // is online/offline and return an appropriate error code. 446 if (!sent_byte_ && 447 http_response_code_ == 0 && 448 no_network_retry_count_ < no_network_max_retries_) { 449 no_network_retry_count_++; 450 retry_task_id_ = MessageLoop::current()->PostDelayedTask( 451 FROM_HERE, 452 base::Bind(&LibcurlHttpFetcher::RetryTimeoutCallback, 453 base::Unretained(this)), 454 TimeDelta::FromSeconds(kNoNetworkRetrySeconds)); 455 LOG(INFO) << "No HTTP response, retry " << no_network_retry_count_; 456 } else if ((!sent_byte_ && !IsHttpResponseSuccess()) || 457 IsHttpResponseError()) { 458 // The transfer completed w/ error and we didn't get any bytes. 459 // If we have another proxy to try, try that. 460 // 461 // TODO(garnold) in fact there are two separate cases here: one case is an 462 // other-than-success return code (including no return code) and no 463 // received bytes, which is necessary due to the way callbacks are 464 // currently processing error conditions; the second is an explicit HTTP 465 // error code, where some data may have been received (as in the case of a 466 // semi-successful multi-chunk fetch). This is a confusing behavior and 467 // should be unified into a complete, coherent interface. 468 LOG(INFO) << "Transfer resulted in an error (" << http_response_code_ 469 << "), " << bytes_downloaded_ << " bytes downloaded"; 470 471 PopProxy(); // Delete the proxy we just gave up on. 472 473 if (HasProxy()) { 474 // We have another proxy. Retry immediately. 475 LOG(INFO) << "Retrying with next proxy setting"; 476 retry_task_id_ = MessageLoop::current()->PostTask( 477 FROM_HERE, 478 base::Bind(&LibcurlHttpFetcher::RetryTimeoutCallback, 479 base::Unretained(this))); 480 } else { 481 // Out of proxies. Give up. 482 LOG(INFO) << "No further proxies, indicating transfer complete"; 483 if (delegate_) 484 delegate_->TransferComplete(this, false); // signal fail 485 return; 486 } 487 } else if ((transfer_size_ >= 0) && (bytes_downloaded_ < transfer_size_)) { 488 if (!ignore_failure_) 489 retry_count_++; 490 LOG(INFO) << "Transfer interrupted after downloading " 491 << bytes_downloaded_ << " of " << transfer_size_ << " bytes. " 492 << transfer_size_ - bytes_downloaded_ << " bytes remaining " 493 << "after " << retry_count_ << " attempt(s)"; 494 495 if (retry_count_ > max_retry_count_) { 496 LOG(INFO) << "Reached max attempts (" << retry_count_ << ")"; 497 if (delegate_) 498 delegate_->TransferComplete(this, false); // signal fail 499 return; 500 } 501 // Need to restart transfer 502 LOG(INFO) << "Restarting transfer to download the remaining bytes"; 503 retry_task_id_ = MessageLoop::current()->PostDelayedTask( 504 FROM_HERE, 505 base::Bind(&LibcurlHttpFetcher::RetryTimeoutCallback, 506 base::Unretained(this)), 507 TimeDelta::FromSeconds(retry_seconds_)); 508 } else { 509 LOG(INFO) << "Transfer completed (" << http_response_code_ 510 << "), " << bytes_downloaded_ << " bytes downloaded"; 511 if (delegate_) { 512 bool success = IsHttpResponseSuccess(); 513 delegate_->TransferComplete(this, success); 514 } 515 return; 516 } 517 // If we reach this point is because TransferComplete() was not called in any 518 // of the previous branches. The delegate is allowed to destroy the object 519 // once TransferComplete is called so this would be illegal. 520 ignore_failure_ = false; 521 } 522 523 size_t LibcurlHttpFetcher::LibcurlWrite(void *ptr, size_t size, size_t nmemb) { 524 // Update HTTP response first. 525 GetHttpResponseCode(); 526 const size_t payload_size = size * nmemb; 527 528 // Do nothing if no payload or HTTP response is an error. 529 if (payload_size == 0 || !IsHttpResponseSuccess()) { 530 LOG(INFO) << "HTTP response unsuccessful (" << http_response_code_ 531 << ") or no payload (" << payload_size << "), nothing to do"; 532 return 0; 533 } 534 535 sent_byte_ = true; 536 { 537 double transfer_size_double; 538 CHECK_EQ(curl_easy_getinfo(curl_handle_, 539 CURLINFO_CONTENT_LENGTH_DOWNLOAD, 540 &transfer_size_double), CURLE_OK); 541 off_t new_transfer_size = static_cast<off_t>(transfer_size_double); 542 if (new_transfer_size > 0) { 543 transfer_size_ = resume_offset_ + new_transfer_size; 544 } 545 } 546 bytes_downloaded_ += payload_size; 547 in_write_callback_ = true; 548 if (delegate_) 549 delegate_->ReceivedBytes(this, ptr, payload_size); 550 in_write_callback_ = false; 551 return payload_size; 552 } 553 554 void LibcurlHttpFetcher::Pause() { 555 if (transfer_paused_) { 556 LOG(ERROR) << "Fetcher already paused."; 557 return; 558 } 559 transfer_paused_ = true; 560 if (!transfer_in_progress_) { 561 // If pause before we started a connection, we don't need to notify curl 562 // about that, we will simply not start the connection later. 563 return; 564 } 565 CHECK(curl_handle_); 566 CHECK_EQ(curl_easy_pause(curl_handle_, CURLPAUSE_ALL), CURLE_OK); 567 } 568 569 void LibcurlHttpFetcher::Unpause() { 570 if (!transfer_paused_) { 571 LOG(ERROR) << "Resume attempted when fetcher not paused."; 572 return; 573 } 574 transfer_paused_ = false; 575 if (restart_transfer_on_unpause_) { 576 restart_transfer_on_unpause_ = false; 577 ResumeTransfer(url_); 578 CurlPerformOnce(); 579 return; 580 } 581 if (!transfer_in_progress_) { 582 // If resumed before starting the connection, there's no need to notify 583 // anybody. We will simply start the connection once it is time. 584 return; 585 } 586 CHECK(curl_handle_); 587 CHECK_EQ(curl_easy_pause(curl_handle_, CURLPAUSE_CONT), CURLE_OK); 588 // Since the transfer is in progress, we need to dispatch a CurlPerformOnce() 589 // now to let the connection continue, otherwise it would be called by the 590 // TimeoutCallback but with a delay. 591 CurlPerformOnce(); 592 } 593 594 // This method sets up callbacks with the MessageLoop. 595 void LibcurlHttpFetcher::SetupMessageLoopSources() { 596 fd_set fd_read; 597 fd_set fd_write; 598 fd_set fd_exc; 599 600 FD_ZERO(&fd_read); 601 FD_ZERO(&fd_write); 602 FD_ZERO(&fd_exc); 603 604 int fd_max = 0; 605 606 // Ask libcurl for the set of file descriptors we should track on its 607 // behalf. 608 CHECK_EQ(curl_multi_fdset(curl_multi_handle_, &fd_read, &fd_write, 609 &fd_exc, &fd_max), CURLM_OK); 610 611 // We should iterate through all file descriptors up to libcurl's fd_max or 612 // the highest one we're tracking, whichever is larger. 613 for (size_t t = 0; t < arraysize(fd_task_maps_); ++t) { 614 if (!fd_task_maps_[t].empty()) 615 fd_max = max(fd_max, fd_task_maps_[t].rbegin()->first); 616 } 617 618 // For each fd, if we're not tracking it, track it. If we are tracking it, but 619 // libcurl doesn't care about it anymore, stop tracking it. After this loop, 620 // there should be exactly as many tasks scheduled in fd_task_maps_[0|1] as 621 // there are read/write fds that we're tracking. 622 for (int fd = 0; fd <= fd_max; ++fd) { 623 // Note that fd_exc is unused in the current version of libcurl so is_exc 624 // should always be false. 625 bool is_exc = FD_ISSET(fd, &fd_exc) != 0; 626 bool must_track[2] = { 627 is_exc || (FD_ISSET(fd, &fd_read) != 0), // track 0 -- read 628 is_exc || (FD_ISSET(fd, &fd_write) != 0) // track 1 -- write 629 }; 630 MessageLoop::WatchMode watch_modes[2] = { 631 MessageLoop::WatchMode::kWatchRead, 632 MessageLoop::WatchMode::kWatchWrite, 633 }; 634 635 for (size_t t = 0; t < arraysize(fd_task_maps_); ++t) { 636 auto fd_task_it = fd_task_maps_[t].find(fd); 637 bool tracked = fd_task_it != fd_task_maps_[t].end(); 638 639 if (!must_track[t]) { 640 // If we have an outstanding io_channel, remove it. 641 if (tracked) { 642 MessageLoop::current()->CancelTask(fd_task_it->second); 643 fd_task_maps_[t].erase(fd_task_it); 644 } 645 continue; 646 } 647 648 // If we are already tracking this fd, continue -- nothing to do. 649 if (tracked) 650 continue; 651 652 // Track a new fd. 653 fd_task_maps_[t][fd] = MessageLoop::current()->WatchFileDescriptor( 654 FROM_HERE, 655 fd, 656 watch_modes[t], 657 true, // persistent 658 base::Bind(&LibcurlHttpFetcher::CurlPerformOnce, 659 base::Unretained(this))); 660 661 static int io_counter = 0; 662 io_counter++; 663 if (io_counter % 50 == 0) { 664 LOG(INFO) << "io_counter = " << io_counter; 665 } 666 } 667 } 668 669 // Set up a timeout callback for libcurl. 670 if (timeout_id_ == MessageLoop::kTaskIdNull) { 671 VLOG(1) << "Setting up timeout source: " << idle_seconds_ << " seconds."; 672 timeout_id_ = MessageLoop::current()->PostDelayedTask( 673 FROM_HERE, 674 base::Bind(&LibcurlHttpFetcher::TimeoutCallback, 675 base::Unretained(this)), 676 TimeDelta::FromSeconds(idle_seconds_)); 677 } 678 } 679 680 void LibcurlHttpFetcher::RetryTimeoutCallback() { 681 retry_task_id_ = MessageLoop::kTaskIdNull; 682 if (transfer_paused_) { 683 restart_transfer_on_unpause_ = true; 684 return; 685 } 686 ResumeTransfer(url_); 687 CurlPerformOnce(); 688 } 689 690 void LibcurlHttpFetcher::TimeoutCallback() { 691 // We always re-schedule the callback, even if we don't want to be called 692 // anymore. We will remove the event source separately if we don't want to 693 // be called back. 694 timeout_id_ = MessageLoop::current()->PostDelayedTask( 695 FROM_HERE, 696 base::Bind(&LibcurlHttpFetcher::TimeoutCallback, base::Unretained(this)), 697 TimeDelta::FromSeconds(idle_seconds_)); 698 699 // CurlPerformOnce() may call CleanUp(), so we need to schedule our callback 700 // first, since it could be canceled by this call. 701 if (transfer_in_progress_) 702 CurlPerformOnce(); 703 } 704 705 void LibcurlHttpFetcher::CleanUp() { 706 MessageLoop::current()->CancelTask(retry_task_id_); 707 retry_task_id_ = MessageLoop::kTaskIdNull; 708 709 MessageLoop::current()->CancelTask(timeout_id_); 710 timeout_id_ = MessageLoop::kTaskIdNull; 711 712 for (size_t t = 0; t < arraysize(fd_task_maps_); ++t) { 713 for (const auto& fd_taks_pair : fd_task_maps_[t]) { 714 if (!MessageLoop::current()->CancelTask(fd_taks_pair.second)) { 715 LOG(WARNING) << "Error canceling the watch task " 716 << fd_taks_pair.second << " for " 717 << (t ? "writing" : "reading") << " the fd " 718 << fd_taks_pair.first; 719 } 720 } 721 fd_task_maps_[t].clear(); 722 } 723 724 if (curl_http_headers_) { 725 curl_slist_free_all(curl_http_headers_); 726 curl_http_headers_ = nullptr; 727 } 728 if (curl_handle_) { 729 if (curl_multi_handle_) { 730 CHECK_EQ(curl_multi_remove_handle(curl_multi_handle_, curl_handle_), 731 CURLM_OK); 732 } 733 curl_easy_cleanup(curl_handle_); 734 curl_handle_ = nullptr; 735 } 736 if (curl_multi_handle_) { 737 CHECK_EQ(curl_multi_cleanup(curl_multi_handle_), CURLM_OK); 738 curl_multi_handle_ = nullptr; 739 } 740 transfer_in_progress_ = false; 741 transfer_paused_ = false; 742 restart_transfer_on_unpause_ = false; 743 } 744 745 void LibcurlHttpFetcher::GetHttpResponseCode() { 746 long http_response_code = 0; // NOLINT(runtime/int) - curl needs long. 747 if (base::StartsWith(url_, "file://", base::CompareCase::INSENSITIVE_ASCII)) { 748 // Fake out a valid response code for file:// URLs. 749 http_response_code_ = 299; 750 } else if (curl_easy_getinfo(curl_handle_, 751 CURLINFO_RESPONSE_CODE, 752 &http_response_code) == CURLE_OK) { 753 http_response_code_ = static_cast<int>(http_response_code); 754 } 755 } 756 757 } // namespace chromeos_update_engine 758
