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//
// Copyright (C) 2009 The Android Open Source Project
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#include "update_engine/libcurl_http_fetcher.h"
#include <netinet/in.h>
#include <resolv.h>
#include <sys/types.h>
#include <unistd.h>
#include <algorithm>
#include <string>
#include <base/bind.h>
#include <base/format_macros.h>
#include <base/location.h>
#include <base/logging.h>
#include <base/strings/string_split.h>
#include <base/strings/string_util.h>
#include <base/strings/stringprintf.h>
#include <base/threading/thread_task_runner_handle.h>
#ifdef __ANDROID__
#include <cutils/qtaguid.h>
#include <private/android_filesystem_config.h>
#endif // __ANDROID__
#include "update_engine/certificate_checker.h"
#include "update_engine/common/hardware_interface.h"
#include "update_engine/common/platform_constants.h"
using base::TimeDelta;
using brillo::MessageLoop;
using std::max;
using std::string;
// This is a concrete implementation of HttpFetcher that uses libcurl to do the
// http work.
namespace chromeos_update_engine {
namespace {
const int kNoNetworkRetrySeconds = 10;
// libcurl's CURLOPT_SOCKOPTFUNCTION callback function. Called after the socket
// is created but before it is connected. This callback tags the created socket
// so the network usage can be tracked in Android.
int LibcurlSockoptCallback(void* /* clientp */,
curl_socket_t curlfd,
curlsocktype /* purpose */) {
#ifdef __ANDROID__
// Socket tag used by all network sockets. See qtaguid kernel module for
// stats.
const int kUpdateEngineSocketTag = 0x55417243; // "CrAU" in little-endian.
qtaguid_tagSocket(curlfd, kUpdateEngineSocketTag, AID_OTA_UPDATE);
#endif // __ANDROID__
return CURL_SOCKOPT_OK;
}
} // namespace
// static
int LibcurlHttpFetcher::LibcurlCloseSocketCallback(void* clientp,
curl_socket_t item) {
#ifdef __ANDROID__
qtaguid_untagSocket(item);
#endif // __ANDROID__
LibcurlHttpFetcher* fetcher = static_cast<LibcurlHttpFetcher*>(clientp);
// Stop watching the socket before closing it.
for (size_t t = 0; t < base::size(fetcher->fd_controller_maps_); ++t) {
fetcher->fd_controller_maps_[t].erase(item);
}
// Documentation for this callback says to return 0 on success or 1 on error.
if (!IGNORE_EINTR(close(item)))
return 0;
return 1;
}
LibcurlHttpFetcher::LibcurlHttpFetcher(ProxyResolver* proxy_resolver,
HardwareInterface* hardware)
: HttpFetcher(proxy_resolver), hardware_(hardware) {
// Dev users want a longer timeout (180 seconds) because they may
// be waiting on the dev server to build an image.
if (!hardware_->IsOfficialBuild())
low_speed_time_seconds_ = kDownloadDevModeLowSpeedTimeSeconds;
if (hardware_->IsOOBEEnabled() && !hardware_->IsOOBEComplete(nullptr))
max_retry_count_ = kDownloadMaxRetryCountOobeNotComplete;
}
LibcurlHttpFetcher::~LibcurlHttpFetcher() {
LOG_IF(ERROR, transfer_in_progress_)
<< "Destroying the fetcher while a transfer is in progress.";
CancelProxyResolution();
CleanUp();
}
bool LibcurlHttpFetcher::GetProxyType(const string& proxy,
curl_proxytype* out_type) {
if (base::StartsWith(
proxy, "socks5://", base::CompareCase::INSENSITIVE_ASCII) ||
base::StartsWith(
proxy, "socks://", base::CompareCase::INSENSITIVE_ASCII)) {
*out_type = CURLPROXY_SOCKS5_HOSTNAME;
return true;
}
if (base::StartsWith(
proxy, "socks4://", base::CompareCase::INSENSITIVE_ASCII)) {
*out_type = CURLPROXY_SOCKS4A;
return true;
}
if (base::StartsWith(
proxy, "http://", base::CompareCase::INSENSITIVE_ASCII) ||
base::StartsWith(
proxy, "https://", base::CompareCase::INSENSITIVE_ASCII)) {
*out_type = CURLPROXY_HTTP;
return true;
}
if (base::StartsWith(proxy, kNoProxy, base::CompareCase::INSENSITIVE_ASCII)) {
// known failure case. don't log.
return false;
}
LOG(INFO) << "Unknown proxy type: " << proxy;
return false;
}
void LibcurlHttpFetcher::ResumeTransfer(const string& url) {
LOG(INFO) << "Starting/Resuming transfer";
CHECK(!transfer_in_progress_);
url_ = url;
curl_multi_handle_ = curl_multi_init();
CHECK(curl_multi_handle_);
curl_handle_ = curl_easy_init();
CHECK(curl_handle_);
ignore_failure_ = false;
// Tag and untag the socket for network usage stats.
curl_easy_setopt(
curl_handle_, CURLOPT_SOCKOPTFUNCTION, LibcurlSockoptCallback);
curl_easy_setopt(
curl_handle_, CURLOPT_CLOSESOCKETFUNCTION, LibcurlCloseSocketCallback);
curl_easy_setopt(curl_handle_, CURLOPT_CLOSESOCKETDATA, this);
CHECK(HasProxy());
bool is_direct = (GetCurrentProxy() == kNoProxy);
LOG(INFO) << "Using proxy: " << (is_direct ? "no" : "yes");
if (is_direct) {
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROXY, ""), CURLE_OK);
} else {
CHECK_EQ(curl_easy_setopt(
curl_handle_, CURLOPT_PROXY, GetCurrentProxy().c_str()),
CURLE_OK);
// Curl seems to require us to set the protocol
curl_proxytype type;
if (GetProxyType(GetCurrentProxy(), &type)) {
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROXYTYPE, type),
CURLE_OK);
}
}
if (post_data_set_) {
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_POST, 1), CURLE_OK);
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_POSTFIELDS, post_data_.data()),
CURLE_OK);
CHECK_EQ(curl_easy_setopt(
curl_handle_, CURLOPT_POSTFIELDSIZE, post_data_.size()),
CURLE_OK);
}
// Setup extra HTTP headers.
if (curl_http_headers_) {
curl_slist_free_all(curl_http_headers_);
curl_http_headers_ = nullptr;
}
for (const auto& header : extra_headers_) {
// curl_slist_append() copies the string.
curl_http_headers_ =
curl_slist_append(curl_http_headers_, header.second.c_str());
}
if (post_data_set_) {
// Set the Content-Type HTTP header, if one was specifically set.
if (post_content_type_ != kHttpContentTypeUnspecified) {
const string content_type_attr = base::StringPrintf(
"Content-Type: %s", GetHttpContentTypeString(post_content_type_));
curl_http_headers_ =
curl_slist_append(curl_http_headers_, content_type_attr.c_str());
} else {
LOG(WARNING) << "no content type set, using libcurl default";
}
}
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_HTTPHEADER, curl_http_headers_),
CURLE_OK);
if (bytes_downloaded_ > 0 || download_length_) {
// Resume from where we left off.
resume_offset_ = bytes_downloaded_;
CHECK_GE(resume_offset_, 0);
// Compute end offset, if one is specified. As per HTTP specification, this
// is an inclusive boundary. Make sure it doesn't overflow.
size_t end_offset = 0;
if (download_length_) {
end_offset = static_cast<size_t>(resume_offset_) + download_length_ - 1;
CHECK_LE((size_t)resume_offset_, end_offset);
}
// Create a string representation of the desired range.
string range_str = base::StringPrintf(
"%" PRIu64 "-", static_cast<uint64_t>(resume_offset_));
if (end_offset)
range_str += std::to_string(end_offset);
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_RANGE, range_str.c_str()),
CURLE_OK);
}
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_WRITEDATA, this), CURLE_OK);
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_WRITEFUNCTION, StaticLibcurlWrite),
CURLE_OK);
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_URL, url_.c_str()), CURLE_OK);
// If the connection drops under |low_speed_limit_bps_| (10
// bytes/sec by default) for |low_speed_time_seconds_| (90 seconds,
// 180 on non-official builds), reconnect.
CHECK_EQ(curl_easy_setopt(
curl_handle_, CURLOPT_LOW_SPEED_LIMIT, low_speed_limit_bps_),
CURLE_OK);
CHECK_EQ(curl_easy_setopt(
curl_handle_, CURLOPT_LOW_SPEED_TIME, low_speed_time_seconds_),
CURLE_OK);
CHECK_EQ(curl_easy_setopt(
curl_handle_, CURLOPT_CONNECTTIMEOUT, connect_timeout_seconds_),
CURLE_OK);
// By default, libcurl doesn't follow redirections. Allow up to
// |kDownloadMaxRedirects| redirections.
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_FOLLOWLOCATION, 1), CURLE_OK);
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_MAXREDIRS, kDownloadMaxRedirects),
CURLE_OK);
// Lock down the appropriate curl options for HTTP or HTTPS depending on
// the url.
if (hardware_->IsOfficialBuild()) {
if (base::StartsWith(
url_, "http://", base::CompareCase::INSENSITIVE_ASCII)) {
SetCurlOptionsForHttp();
} else if (base::StartsWith(
url_, "https://", base::CompareCase::INSENSITIVE_ASCII)) {
SetCurlOptionsForHttps();
#ifdef __ANDROID__
} else if (base::StartsWith(
url_, "file://", base::CompareCase::INSENSITIVE_ASCII)) {
SetCurlOptionsForFile();
#endif // __ANDROID__
} else {
LOG(ERROR) << "Received invalid URI: " << url_;
// Lock down to no protocol supported for the transfer.
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROTOCOLS, 0), CURLE_OK);
}
} else {
LOG(INFO) << "Not setting http(s) curl options because we are "
<< "running a dev/test image";
}
CHECK_EQ(curl_multi_add_handle(curl_multi_handle_, curl_handle_), CURLM_OK);
transfer_in_progress_ = true;
}
// Lock down only the protocol in case of HTTP.
void LibcurlHttpFetcher::SetCurlOptionsForHttp() {
LOG(INFO) << "Setting up curl options for HTTP";
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROTOCOLS, CURLPROTO_HTTP),
CURLE_OK);
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_REDIR_PROTOCOLS, CURLPROTO_HTTP),
CURLE_OK);
}
// Security lock-down in official builds: makes sure that peer certificate
// verification is enabled, restricts the set of trusted certificates,
// restricts protocols to HTTPS, restricts ciphers to HIGH.
void LibcurlHttpFetcher::SetCurlOptionsForHttps() {
LOG(INFO) << "Setting up curl options for HTTPS";
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_VERIFYPEER, 1), CURLE_OK);
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_VERIFYHOST, 2), CURLE_OK);
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_CAINFO, nullptr), CURLE_OK);
CHECK_EQ(curl_easy_setopt(
curl_handle_, CURLOPT_CAPATH, constants::kCACertificatesPath),
CURLE_OK);
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROTOCOLS, CURLPROTO_HTTPS),
CURLE_OK);
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_REDIR_PROTOCOLS, CURLPROTO_HTTPS),
CURLE_OK);
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_CIPHER_LIST, "HIGH:!ADH"),
CURLE_OK);
if (server_to_check_ != ServerToCheck::kNone) {
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_SSL_CTX_DATA, &server_to_check_),
CURLE_OK);
CHECK_EQ(curl_easy_setopt(curl_handle_,
CURLOPT_SSL_CTX_FUNCTION,
CertificateChecker::ProcessSSLContext),
CURLE_OK);
}
}
// Lock down only the protocol in case of a local file.
void LibcurlHttpFetcher::SetCurlOptionsForFile() {
LOG(INFO) << "Setting up curl options for FILE";
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_PROTOCOLS, CURLPROTO_FILE),
CURLE_OK);
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_REDIR_PROTOCOLS, CURLPROTO_FILE),
CURLE_OK);
}
// Begins the transfer, which must not have already been started.
void LibcurlHttpFetcher::BeginTransfer(const string& url) {
CHECK(!transfer_in_progress_);
url_ = url;
auto closure =
base::Bind(&LibcurlHttpFetcher::ProxiesResolved, base::Unretained(this));
ResolveProxiesForUrl(url_, closure);
}
void LibcurlHttpFetcher::ProxiesResolved() {
transfer_size_ = -1;
resume_offset_ = 0;
retry_count_ = 0;
no_network_retry_count_ = 0;
http_response_code_ = 0;
terminate_requested_ = false;
sent_byte_ = false;
// If we are paused, we delay these two operations until Unpause is called.
if (transfer_paused_) {
restart_transfer_on_unpause_ = true;
return;
}
ResumeTransfer(url_);
CurlPerformOnce();
}
void LibcurlHttpFetcher::ForceTransferTermination() {
CancelProxyResolution();
CleanUp();
if (delegate_) {
// Note that after the callback returns this object may be destroyed.
delegate_->TransferTerminated(this);
}
}
void LibcurlHttpFetcher::TerminateTransfer() {
if (in_write_callback_) {
terminate_requested_ = true;
} else {
ForceTransferTermination();
}
}
void LibcurlHttpFetcher::SetHeader(const string& header_name,
const string& header_value) {
string header_line = header_name + ": " + header_value;
// Avoid the space if no data on the right side of the semicolon.
if (header_value.empty())
header_line = header_name + ":";
TEST_AND_RETURN(header_line.find('\n') == string::npos);
TEST_AND_RETURN(header_name.find(':') == string::npos);
extra_headers_[base::ToLowerASCII(header_name)] = header_line;
}
// Inputs: header_name, header_value
// Example:
// extra_headers_ = { {"foo":"foo: 123"}, {"bar":"bar:"} }
// string tmp = "gibberish";
// Case 1:
// GetHeader("foo", &tmp) -> tmp = "123", return true.
// Case 2:
// GetHeader("bar", &tmp) -> tmp = "", return true.
// Case 3:
// GetHeader("moo", &tmp) -> tmp = "", return false.
bool LibcurlHttpFetcher::GetHeader(const string& header_name,
string* header_value) const {
// Initially clear |header_value| to handle both success and failures without
// leaving |header_value| in a unclear state.
header_value->clear();
auto header_key = base::ToLowerASCII(header_name);
auto header_line_itr = extra_headers_.find(header_key);
// If the |header_name| was never set, indicate so by returning false.
if (header_line_itr == extra_headers_.end())
return false;
// From |SetHeader()| the check for |header_name| to not include ":" is
// verified, so finding the first index of ":" is a safe operation.
auto header_line = header_line_itr->second;
*header_value = header_line.substr(header_line.find(':') + 1);
// The following is neccessary to remove the leading ' ' before the header
// value that was place only if |header_value| passed to |SetHeader()| was
// a non-empty string.
header_value->erase(0, 1);
return true;
}
void LibcurlHttpFetcher::CurlPerformOnce() {
CHECK(transfer_in_progress_);
int running_handles = 0;
CURLMcode retcode = CURLM_CALL_MULTI_PERFORM;
// libcurl may request that we immediately call curl_multi_perform after it
// returns, so we do. libcurl promises that curl_multi_perform will not block.
while (CURLM_CALL_MULTI_PERFORM == retcode) {
retcode = curl_multi_perform(curl_multi_handle_, &running_handles);
if (terminate_requested_) {
ForceTransferTermination();
return;
}
}
// When retcode is not |CURLM_OK| at this point, libcurl has an internal error
// that it is less likely to recover from (libcurl bug, out-of-memory, etc.).
// In case of an update check, we send UMA metrics and log the error.
if (is_update_check_ &&
(retcode == CURLM_OUT_OF_MEMORY || retcode == CURLM_INTERNAL_ERROR)) {
auxiliary_error_code_ = ErrorCode::kInternalLibCurlError;
LOG(ERROR) << "curl_multi_perform is in an unrecoverable error condition: "
<< retcode;
} else if (retcode != CURLM_OK) {
LOG(ERROR) << "curl_multi_perform returns error: " << retcode;
}
// If the transfer completes while paused, we should ignore the failure once
// the fetcher is unpaused.
if (running_handles == 0 && transfer_paused_ && !ignore_failure_) {
LOG(INFO) << "Connection closed while paused, ignoring failure.";
ignore_failure_ = true;
}
if (running_handles != 0 || transfer_paused_) {
// There's either more work to do or we are paused, so we just keep the
// file descriptors to watch up to date and exit, until we are done with the
// work and we are not paused.
//
// When there's no |base::SingleThreadTaskRunner| on current thread, it's
// not possible to watch file descriptors. Just poll it later. This usually
// happens if |brillo::FakeMessageLoop| is used.
if (!base::ThreadTaskRunnerHandle::IsSet()) {
MessageLoop::current()->PostDelayedTask(
FROM_HERE,
base::Bind(&LibcurlHttpFetcher::CurlPerformOnce,
base::Unretained(this)),
TimeDelta::FromSeconds(1));
return;
}
SetupMessageLoopSources();
return;
}
// At this point, the transfer was completed in some way (error, connection
// closed or download finished).
GetHttpResponseCode();
if (http_response_code_) {
LOG(INFO) << "HTTP response code: " << http_response_code_;
no_network_retry_count_ = 0;
unresolved_host_state_machine_.UpdateState(false);
} else {
LOG(ERROR) << "Unable to get http response code.";
CURLcode curl_code = GetCurlCode();
LOG(ERROR) << "Return code for the transfer: " << curl_code;
if (curl_code == CURLE_COULDNT_RESOLVE_HOST) {
LOG(ERROR) << "libcurl can not resolve host.";
unresolved_host_state_machine_.UpdateState(true);
auxiliary_error_code_ = ErrorCode::kUnresolvedHostError;
}
}
// we're done!
CleanUp();
if (unresolved_host_state_machine_.GetState() ==
UnresolvedHostStateMachine::State::kRetry) {
// Based on
// https://curl.haxx.se/docs/todo.html#updated_DNS_server_while_running,
// update_engine process should call res_init() and unconditionally retry.
res_init();
no_network_max_retries_++;
LOG(INFO) << "Will retry after reloading resolv.conf because last attempt "
"failed to resolve host.";
} else if (unresolved_host_state_machine_.GetState() ==
UnresolvedHostStateMachine::State::kRetriedSuccess) {
auxiliary_error_code_ = ErrorCode::kUnresolvedHostRecovered;
}
// TODO(petkov): This temporary code tries to deal with the case where the
// update engine performs an update check while the network is not ready
// (e.g., right after resume). Longer term, we should check if the network
// is online/offline and return an appropriate error code.
if (!sent_byte_ && http_response_code_ == 0 &&
no_network_retry_count_ < no_network_max_retries_) {
no_network_retry_count_++;
retry_task_id_ = MessageLoop::current()->PostDelayedTask(
FROM_HERE,
base::Bind(&LibcurlHttpFetcher::RetryTimeoutCallback,
base::Unretained(this)),
TimeDelta::FromSeconds(kNoNetworkRetrySeconds));
LOG(INFO) << "No HTTP response, retry " << no_network_retry_count_;
} else if ((!sent_byte_ && !IsHttpResponseSuccess()) ||
IsHttpResponseError()) {
// The transfer completed w/ error and we didn't get any bytes.
// If we have another proxy to try, try that.
//
// TODO(garnold) in fact there are two separate cases here: one case is an
// other-than-success return code (including no return code) and no
// received bytes, which is necessary due to the way callbacks are
// currently processing error conditions; the second is an explicit HTTP
// error code, where some data may have been received (as in the case of a
// semi-successful multi-chunk fetch). This is a confusing behavior and
// should be unified into a complete, coherent interface.
LOG(INFO) << "Transfer resulted in an error (" << http_response_code_
<< "), " << bytes_downloaded_ << " bytes downloaded";
PopProxy(); // Delete the proxy we just gave up on.
if (HasProxy()) {
// We have another proxy. Retry immediately.
LOG(INFO) << "Retrying with next proxy setting";
retry_task_id_ = MessageLoop::current()->PostTask(
FROM_HERE,
base::Bind(&LibcurlHttpFetcher::RetryTimeoutCallback,
base::Unretained(this)));
} else {
// Out of proxies. Give up.
LOG(INFO) << "No further proxies, indicating transfer complete";
if (delegate_)
delegate_->TransferComplete(this, false); // signal fail
return;
}
} else if ((transfer_size_ >= 0) && (bytes_downloaded_ < transfer_size_)) {
if (!ignore_failure_)
retry_count_++;
LOG(INFO) << "Transfer interrupted after downloading " << bytes_downloaded_
<< " of " << transfer_size_ << " bytes. "
<< transfer_size_ - bytes_downloaded_ << " bytes remaining "
<< "after " << retry_count_ << " attempt(s)";
if (retry_count_ > max_retry_count_) {
LOG(INFO) << "Reached max attempts (" << retry_count_ << ")";
if (delegate_)
delegate_->TransferComplete(this, false); // signal fail
return;
}
// Need to restart transfer
LOG(INFO) << "Restarting transfer to download the remaining bytes";
retry_task_id_ = MessageLoop::current()->PostDelayedTask(
FROM_HERE,
base::Bind(&LibcurlHttpFetcher::RetryTimeoutCallback,
base::Unretained(this)),
TimeDelta::FromSeconds(retry_seconds_));
} else {
LOG(INFO) << "Transfer completed (" << http_response_code_ << "), "
<< bytes_downloaded_ << " bytes downloaded";
if (delegate_) {
bool success = IsHttpResponseSuccess();
delegate_->TransferComplete(this, success);
}
return;
}
// If we reach this point is because TransferComplete() was not called in any
// of the previous branches. The delegate is allowed to destroy the object
// once TransferComplete is called so this would be illegal.
ignore_failure_ = false;
}
size_t LibcurlHttpFetcher::LibcurlWrite(void* ptr, size_t size, size_t nmemb) {
// Update HTTP response first.
GetHttpResponseCode();
const size_t payload_size = size * nmemb;
// Do nothing if no payload or HTTP response is an error.
if (payload_size == 0 || !IsHttpResponseSuccess()) {
LOG(INFO) << "HTTP response unsuccessful (" << http_response_code_
<< ") or no payload (" << payload_size << "), nothing to do";
return 0;
}
sent_byte_ = true;
{
double transfer_size_double;
CHECK_EQ(curl_easy_getinfo(curl_handle_,
CURLINFO_CONTENT_LENGTH_DOWNLOAD,
&transfer_size_double),
CURLE_OK);
off_t new_transfer_size = static_cast<off_t>(transfer_size_double);
if (new_transfer_size > 0) {
transfer_size_ = resume_offset_ + new_transfer_size;
}
}
bytes_downloaded_ += payload_size;
if (delegate_) {
in_write_callback_ = true;
auto should_terminate = !delegate_->ReceivedBytes(this, ptr, payload_size);
in_write_callback_ = false;
if (should_terminate) {
LOG(INFO) << "Requesting libcurl to terminate transfer.";
// Returning an amount that differs from the received size signals an
// error condition to libcurl, which will cause the transfer to be
// aborted.
return 0;
}
}
return payload_size;
}
void LibcurlHttpFetcher::Pause() {
if (transfer_paused_) {
LOG(ERROR) << "Fetcher already paused.";
return;
}
transfer_paused_ = true;
if (!transfer_in_progress_) {
// If pause before we started a connection, we don't need to notify curl
// about that, we will simply not start the connection later.
return;
}
CHECK(curl_handle_);
CHECK_EQ(curl_easy_pause(curl_handle_, CURLPAUSE_ALL), CURLE_OK);
}
void LibcurlHttpFetcher::Unpause() {
if (!transfer_paused_) {
LOG(ERROR) << "Resume attempted when fetcher not paused.";
return;
}
transfer_paused_ = false;
if (restart_transfer_on_unpause_) {
restart_transfer_on_unpause_ = false;
ResumeTransfer(url_);
CurlPerformOnce();
return;
}
if (!transfer_in_progress_) {
// If resumed before starting the connection, there's no need to notify
// anybody. We will simply start the connection once it is time.
return;
}
CHECK(curl_handle_);
CHECK_EQ(curl_easy_pause(curl_handle_, CURLPAUSE_CONT), CURLE_OK);
// Since the transfer is in progress, we need to dispatch a CurlPerformOnce()
// now to let the connection continue, otherwise it would be called by the
// TimeoutCallback but with a delay.
CurlPerformOnce();
}
// This method sets up callbacks with the MessageLoop.
void LibcurlHttpFetcher::SetupMessageLoopSources() {
fd_set fd_read;
fd_set fd_write;
fd_set fd_exc;
FD_ZERO(&fd_read);
FD_ZERO(&fd_write);
FD_ZERO(&fd_exc);
int fd_max = 0;
// Ask libcurl for the set of file descriptors we should track on its
// behalf.
CHECK_EQ(curl_multi_fdset(
curl_multi_handle_, &fd_read, &fd_write, &fd_exc, &fd_max),
CURLM_OK);
// We should iterate through all file descriptors up to libcurl's fd_max or
// the highest one we're tracking, whichever is larger.
for (size_t t = 0; t < base::size(fd_controller_maps_); ++t) {
if (!fd_controller_maps_[t].empty())
fd_max = max(fd_max, fd_controller_maps_[t].rbegin()->first);
}
// For each fd, if we're not tracking it, track it. If we are tracking it, but
// libcurl doesn't care about it anymore, stop tracking it. After this loop,
// there should be exactly as many tasks scheduled in
// fd_controller_maps_[0|1] as there are read/write fds that we're tracking.
for (int fd = 0; fd <= fd_max; ++fd) {
// Note that fd_exc is unused in the current version of libcurl so is_exc
// should always be false.
bool is_exc = FD_ISSET(fd, &fd_exc) != 0;
bool must_track[2] = {
is_exc || (FD_ISSET(fd, &fd_read) != 0), // track 0 -- read
is_exc || (FD_ISSET(fd, &fd_write) != 0) // track 1 -- write
};
for (size_t t = 0; t < base::size(fd_controller_maps_); ++t) {
bool tracked =
fd_controller_maps_[t].find(fd) != fd_controller_maps_[t].end();
if (!must_track[t]) {
// If we have an outstanding io_channel, remove it.
fd_controller_maps_[t].erase(fd);
continue;
}
// If we are already tracking this fd, continue -- nothing to do.
if (tracked)
continue;
// Track a new fd.
switch (t) {
case 0: // Read
fd_controller_maps_[t][fd] =
base::FileDescriptorWatcher::WatchReadable(
fd,
base::BindRepeating(&LibcurlHttpFetcher::CurlPerformOnce,
base::Unretained(this)));
break;
case 1: // Write
fd_controller_maps_[t][fd] =
base::FileDescriptorWatcher::WatchWritable(
fd,
base::BindRepeating(&LibcurlHttpFetcher::CurlPerformOnce,
base::Unretained(this)));
}
static int io_counter = 0;
io_counter++;
if (io_counter % 50 == 0) {
LOG(INFO) << "io_counter = " << io_counter;
}
}
}
// Set up a timeout callback for libcurl.
if (timeout_id_ == MessageLoop::kTaskIdNull) {
VLOG(1) << "Setting up timeout source: " << idle_seconds_ << " seconds.";
timeout_id_ = MessageLoop::current()->PostDelayedTask(
FROM_HERE,
base::Bind(&LibcurlHttpFetcher::TimeoutCallback,
base::Unretained(this)),
TimeDelta::FromSeconds(idle_seconds_));
}
}
void LibcurlHttpFetcher::RetryTimeoutCallback() {
retry_task_id_ = MessageLoop::kTaskIdNull;
if (transfer_paused_) {
restart_transfer_on_unpause_ = true;
return;
}
ResumeTransfer(url_);
CurlPerformOnce();
}
void LibcurlHttpFetcher::TimeoutCallback() {
// We always re-schedule the callback, even if we don't want to be called
// anymore. We will remove the event source separately if we don't want to
// be called back.
timeout_id_ = MessageLoop::current()->PostDelayedTask(
FROM_HERE,
base::Bind(&LibcurlHttpFetcher::TimeoutCallback, base::Unretained(this)),
TimeDelta::FromSeconds(idle_seconds_));
// CurlPerformOnce() may call CleanUp(), so we need to schedule our callback
// first, since it could be canceled by this call.
if (transfer_in_progress_)
CurlPerformOnce();
}
void LibcurlHttpFetcher::CleanUp() {
MessageLoop::current()->CancelTask(retry_task_id_);
retry_task_id_ = MessageLoop::kTaskIdNull;
MessageLoop::current()->CancelTask(timeout_id_);
timeout_id_ = MessageLoop::kTaskIdNull;
for (size_t t = 0; t < base::size(fd_controller_maps_); ++t) {
fd_controller_maps_[t].clear();
}
if (curl_http_headers_) {
curl_slist_free_all(curl_http_headers_);
curl_http_headers_ = nullptr;
}
if (curl_handle_) {
if (curl_multi_handle_) {
CHECK_EQ(curl_multi_remove_handle(curl_multi_handle_, curl_handle_),
CURLM_OK);
}
curl_easy_cleanup(curl_handle_);
curl_handle_ = nullptr;
}
if (curl_multi_handle_) {
CHECK_EQ(curl_multi_cleanup(curl_multi_handle_), CURLM_OK);
curl_multi_handle_ = nullptr;
}
transfer_in_progress_ = false;
transfer_paused_ = false;
restart_transfer_on_unpause_ = false;
}
void LibcurlHttpFetcher::GetHttpResponseCode() {
long http_response_code = 0; // NOLINT(runtime/int) - curl needs long.
if (base::StartsWith(url_, "file://", base::CompareCase::INSENSITIVE_ASCII)) {
// Fake out a valid response code for file:// URLs.
http_response_code_ = 299;
} else if (curl_easy_getinfo(curl_handle_,
CURLINFO_RESPONSE_CODE,
&http_response_code) == CURLE_OK) {
http_response_code_ = static_cast<int>(http_response_code);
} else {
LOG(ERROR) << "Unable to get http response code from curl_easy_getinfo";
}
}
CURLcode LibcurlHttpFetcher::GetCurlCode() {
CURLcode curl_code = CURLE_OK;
while (true) {
// Repeated calls to |curl_multi_info_read| will return a new struct each
// time, until a NULL is returned as a signal that there is no more to get
// at this point.
int msgs_in_queue;
CURLMsg* curl_msg =
curl_multi_info_read(curl_multi_handle_, &msgs_in_queue);
if (curl_msg == nullptr)
break;
// When |curl_msg| is |CURLMSG_DONE|, a transfer of an easy handle is done,
// and then data contains the return code for this transfer.
if (curl_msg->msg == CURLMSG_DONE) {
// Make sure |curl_multi_handle_| has one and only one easy handle
// |curl_handle_|.
CHECK_EQ(curl_handle_, curl_msg->easy_handle);
// Transfer return code reference:
// https://curl.haxx.se/libcurl/c/libcurl-errors.html
curl_code = curl_msg->data.result;
}
}
// Gets connection error if exists.
long connect_error = 0; // NOLINT(runtime/int) - curl needs long.
CURLcode res =
curl_easy_getinfo(curl_handle_, CURLINFO_OS_ERRNO, &connect_error);
if (res == CURLE_OK && connect_error) {
LOG(ERROR) << "Connect error code from the OS: " << connect_error;
}
return curl_code;
}
void UnresolvedHostStateMachine::UpdateState(bool failed_to_resolve_host) {
switch (state_) {
case State::kInit:
if (failed_to_resolve_host) {
state_ = State::kRetry;
}
break;
case State::kRetry:
if (failed_to_resolve_host) {
state_ = State::kNotRetry;
} else {
state_ = State::kRetriedSuccess;
}
break;
case State::kNotRetry:
break;
case State::kRetriedSuccess:
break;
default:
NOTREACHED();
break;
}
}
} // namespace chromeos_update_engine