blob: 9d3229359aba7cc89334a9628e73635474b0fff4 [file] [log] [blame]
// Copyright (c) 2009 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "update_engine/libcurl_http_fetcher.h"
#include <algorithm>
#include <string>
#include <base/bind.h>
#include <base/location.h>
#include <base/logging.h>
#include <base/strings/string_util.h>
#include <base/strings/stringprintf.h>
#include "update_engine/certificate_checker.h"
#include "update_engine/hardware_interface.h"
using base::TimeDelta;
using chromeos::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;
const char kCACertificatesPath[] = "/usr/share/chromeos-ca-certificates";
} // namespace
LibcurlHttpFetcher::~LibcurlHttpFetcher() {
LOG_IF(ERROR, transfer_in_progress_)
<< "Destroying the fetcher while a transfer is in progress.";
CleanUp();
}
bool LibcurlHttpFetcher::GetProxyType(const string& proxy,
curl_proxytype* out_type) {
if (base::StartsWithASCII(proxy, "socks5://", true) ||
base::StartsWithASCII(proxy, "socks://", true)) {
*out_type = CURLPROXY_SOCKS5_HOSTNAME;
return true;
}
if (base::StartsWithASCII(proxy, "socks4://", true)) {
*out_type = CURLPROXY_SOCKS4A;
return true;
}
if (base::StartsWithASCII(proxy, "http://", true) ||
base::StartsWithASCII(proxy, "https://", true)) {
*out_type = CURLPROXY_HTTP;
return true;
}
if (base::StartsWithASCII(proxy, kNoProxy, true)) {
// 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_);
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);
// Set the Content-Type HTTP header, if one was specifically set.
CHECK(!curl_http_headers_);
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(nullptr,
content_type_attr.c_str());
CHECK(curl_http_headers_);
CHECK_EQ(
curl_easy_setopt(curl_handle_, CURLOPT_HTTPHEADER,
curl_http_headers_),
CURLE_OK);
} else {
LOG(WARNING) << "no content type set, using libcurl default";
}
}
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 = (end_offset ?
base::StringPrintf("%jd-%zu", resume_offset_,
end_offset) :
base::StringPrintf("%jd-", resume_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 (GetSystemState()->hardware()->IsOfficialBuild()) {
if (base::StartsWithASCII(url_, "http://", false))
SetCurlOptionsForHttp();
else
SetCurlOptionsForHttps();
} 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_CAPATH, 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 (check_certificate_ != CertificateChecker::kNone) {
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_CTX_DATA,
&check_certificate_),
CURLE_OK);
CHECK_EQ(curl_easy_setopt(curl_handle_, CURLOPT_SSL_CTX_FUNCTION,
CertificateChecker::ProcessSSLContext),
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));
if (!ResolveProxiesForUrl(url_, closure)) {
LOG(ERROR) << "Couldn't resolve proxies";
if (delegate_)
delegate_->TransferComplete(this, false);
}
}
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;
ResumeTransfer(url_);
CurlPerformOnce();
}
void LibcurlHttpFetcher::ForceTransferTermination() {
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::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;
}
}
if (0 == running_handles) {
GetHttpResponseCode();
if (http_response_code_) {
LOG(INFO) << "HTTP response code: " << http_response_code_;
no_network_retry_count_ = 0;
} else {
LOG(ERROR) << "Unable to get http response code.";
}
// we're done!
CleanUp();
// 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_++;
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_;
return;
}
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";
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
}
} else if ((transfer_size_ >= 0) && (bytes_downloaded_ < transfer_size_)) {
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
} else {
// Need to restart transfer
LOG(INFO) << "Restarting transfer to download the remaining bytes";
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);
}
}
} else {
// set up callback
SetupMessageLoopSources();
}
}
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;
in_write_callback_ = true;
if (delegate_)
delegate_->ReceivedBytes(this, ptr, payload_size);
in_write_callback_ = false;
return payload_size;
}
void LibcurlHttpFetcher::Pause() {
CHECK(curl_handle_);
CHECK(transfer_in_progress_);
CHECK_EQ(curl_easy_pause(curl_handle_, CURLPAUSE_ALL), CURLE_OK);
}
void LibcurlHttpFetcher::Unpause() {
CHECK(curl_handle_);
CHECK(transfer_in_progress_);
CHECK_EQ(curl_easy_pause(curl_handle_, CURLPAUSE_CONT), CURLE_OK);
}
// 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 < arraysize(fd_task_maps_); ++t) {
if (!fd_task_maps_[t].empty())
fd_max = max(fd_max, fd_task_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_task_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
};
MessageLoop::WatchMode watch_modes[2] = {
MessageLoop::WatchMode::kWatchRead,
MessageLoop::WatchMode::kWatchWrite,
};
for (size_t t = 0; t < arraysize(fd_task_maps_); ++t) {
auto fd_task_it = fd_task_maps_[t].find(fd);
bool tracked = fd_task_it != fd_task_maps_[t].end();
if (!must_track[t]) {
// If we have an outstanding io_channel, remove it.
if (tracked) {
MessageLoop::current()->CancelTask(fd_task_it->second);
fd_task_maps_[t].erase(fd_task_it);
}
continue;
}
// If we are already tracking this fd, continue -- nothing to do.
if (tracked)
continue;
// Track a new fd.
fd_task_maps_[t][fd] = MessageLoop::current()->WatchFileDescriptor(
FROM_HERE,
fd,
watch_modes[t],
true, // persistent
base::Bind(&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) {
LOG(INFO) << "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() {
ResumeTransfer(url_);
CurlPerformOnce();
}
void LibcurlHttpFetcher::TimeoutCallback() {
if (transfer_in_progress_)
CurlPerformOnce();
// 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_));
}
void LibcurlHttpFetcher::CleanUp() {
MessageLoop::current()->CancelTask(timeout_id_);
timeout_id_ = MessageLoop::kTaskIdNull;
for (size_t t = 0; t < arraysize(fd_task_maps_); ++t) {
for (const auto& fd_taks_pair : fd_task_maps_[t]) {
if (!MessageLoop::current()->CancelTask(fd_taks_pair.second)) {
LOG(WARNING) << "Error canceling the watch task "
<< fd_taks_pair.second << " for "
<< (t ? "writing" : "reading") << " the fd "
<< fd_taks_pair.first;
}
}
fd_task_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;
}
void LibcurlHttpFetcher::GetHttpResponseCode() {
long http_response_code = 0; // NOLINT(runtime/int) - curl needs long.
if (curl_easy_getinfo(curl_handle_,
CURLINFO_RESPONSE_CODE,
&http_response_code) == CURLE_OK) {
http_response_code_ = static_cast<int>(http_response_code);
}
}
} // namespace chromeos_update_engine