Adding upstream version 14.2.21.upstream/14.2.21upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1255 insertions, 0 deletions

diff --git a/src/rgw/rgw_http_client.cc b/src/rgw/rgw_http_client.cc
new file mode 100644
index 00000000..18f7a4ad
--- /dev/null
+++ b/src/rgw/rgw_http_client.cc
@@ -0,0 +1,1255 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "include/compat.h"
+#include "common/errno.h"
+
+#include <boost/utility/string_ref.hpp>
+
+#include <curl/curl.h>
+#include <curl/easy.h>
+#include <curl/multi.h>
+
+#include "rgw_common.h"
+#include "rgw_http_client.h"
+#include "rgw_http_errors.h"
+#include "common/async/completion.h"
+#include "common/RefCountedObj.h"
+
+#include "rgw_coroutine.h"
+
+#include <atomic>
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_rgw
+
+RGWHTTPManager *rgw_http_manager;
+
+struct RGWCurlHandle;
+
+static void do_curl_easy_cleanup(RGWCurlHandle *curl_handle);
+
+struct rgw_http_req_data : public RefCountedObject {
+  RGWCurlHandle *curl_handle{nullptr};
+  curl_slist *h{nullptr};
+  uint64_t id;
+  int ret{0};
+  std::atomic<bool> done = { false };
+  RGWHTTPClient *client{nullptr};
+  rgw_io_id control_io_id;
+  void *user_info{nullptr};
+  bool registered{false};
+  RGWHTTPManager *mgr{nullptr};
+  char error_buf[CURL_ERROR_SIZE];
+  bool write_paused{false};
+  bool read_paused{false};
+
+  Mutex lock;
+  Cond cond;
+
+  using Signature = void(boost::system::error_code);
+  using Completion = ceph::async::Completion<Signature>;
+  std::unique_ptr<Completion> completion;
+
+  rgw_http_req_data() : id(-1), lock("rgw_http_req_data::lock") {
+    // FIPS zeroization audit 20191115: this memset is not security related.
+    memset(error_buf, 0, sizeof(error_buf));
+  }
+
+  template <typename ExecutionContext, typename CompletionToken>
+  auto async_wait(ExecutionContext& ctx, CompletionToken&& token) {
+    boost::asio::async_completion<CompletionToken, Signature> init(token);
+    auto& handler = init.completion_handler;
+    {
+      std::unique_lock l{lock};
+      completion = Completion::create(ctx.get_executor(), std::move(handler));
+    }
+    return init.result.get();
+  }
+  int wait(optional_yield y) {
+    if (done) {
+      return ret;
+    }
+#ifdef HAVE_BOOST_CONTEXT
+    if (y) {
+      auto& context = y.get_io_context();
+      auto& yield = y.get_yield_context();
+      boost::system::error_code ec;
+      async_wait(context, yield[ec]);
+      return -ec.value();
+    }
+#endif
+    Mutex::Locker l(lock);
+    cond.Wait(lock);
+    return ret;
+  }
+
+  void set_state(int bitmask);
+
+  void finish(int r, long http_status = -1) {
+    Mutex::Locker l(lock);
+    if (http_status != -1) {
+      if (client) {
+        client->set_http_status(http_status);
+      }
+    }
+    ret = r;
+    if (curl_handle)
+      do_curl_easy_cleanup(curl_handle);
+
+    if (h)
+      curl_slist_free_all(h);
+
+    curl_handle = NULL;
+    h = NULL;
+    done = true;
+    if (completion) {
+      boost::system::error_code ec(-ret, boost::system::system_category());
+      Completion::post(std::move(completion), ec);
+    } else {
+      cond.Signal();
+    }
+  }
+
+  bool is_done() {
+    return done;
+  }
+
+  int get_retcode() {
+    Mutex::Locker l(lock);
+    return ret;
+  }
+  
+  RGWHTTPManager *get_manager() {
+    Mutex::Locker l(lock);
+    return mgr;
+  }
+
+  CURL *get_easy_handle() const;
+};
+
+struct RGWCurlHandle {
+  int uses;
+  mono_time lastuse;
+  CURL* h;
+
+  explicit RGWCurlHandle(CURL* h) : uses(0), h(h) {};
+  CURL* operator*() {
+    return this->h;
+  }
+};
+
+void rgw_http_req_data::set_state(int bitmask) {
+  /* no need to lock here, moreover curl_easy_pause() might trigger
+   * the data receive callback :/
+   */
+  CURLcode rc = curl_easy_pause(**curl_handle, bitmask);
+  if (rc != CURLE_OK) {
+    dout(0) << "ERROR: curl_easy_pause() returned rc=" << rc << dendl;
+  }
+}
+
+#define MAXIDLE 5
+class RGWCurlHandles : public Thread {
+public:
+  Mutex cleaner_lock;
+  std::vector<RGWCurlHandle*>saved_curl;
+  int cleaner_shutdown;
+  Cond cleaner_cond;
+
+  RGWCurlHandles() :
+    cleaner_lock{"RGWCurlHandles::cleaner_lock"},
+    cleaner_shutdown{0} {
+  }
+
+  RGWCurlHandle* get_curl_handle();
+  void release_curl_handle_now(RGWCurlHandle* curl);
+  void release_curl_handle(RGWCurlHandle* curl);
+  void flush_curl_handles();
+  void* entry();
+  void stop();
+};
+
+RGWCurlHandle* RGWCurlHandles::get_curl_handle() {
+  RGWCurlHandle* curl = 0;
+  CURL* h;
+  {
+    Mutex::Locker lock(cleaner_lock);
+    if (!saved_curl.empty()) {
+      curl = *saved_curl.begin();
+      saved_curl.erase(saved_curl.begin());
+    }
+  }
+  if (curl) {
+  } else if ((h = curl_easy_init())) {
+    curl = new RGWCurlHandle{h};
+  } else {
+    // curl = 0;
+  }
+  return curl;
+}
+
+void RGWCurlHandles::release_curl_handle_now(RGWCurlHandle* curl)
+{
+  curl_easy_cleanup(**curl);
+  delete curl;
+}
+
+void RGWCurlHandles::release_curl_handle(RGWCurlHandle* curl)
+{
+  if (cleaner_shutdown) {
+    release_curl_handle_now(curl);
+  } else {
+    curl_easy_reset(**curl);
+    Mutex::Locker lock(cleaner_lock);
+    curl->lastuse = mono_clock::now();
+    saved_curl.insert(saved_curl.begin(), 1, curl);
+  }
+}
+
+void* RGWCurlHandles::entry()
+{
+  RGWCurlHandle* curl;
+  Mutex::Locker lock(cleaner_lock);
+
+  for (;;) {
+    if (cleaner_shutdown) {
+      if (saved_curl.empty())
+        break;
+    } else {
+      utime_t release = ceph_clock_now() + utime_t(MAXIDLE,0);
+      cleaner_cond.WaitUntil(cleaner_lock, release);
+    }
+    mono_time now = mono_clock::now();
+    while (!saved_curl.empty()) {
+      auto cend = saved_curl.end();
+      --cend;
+      curl = *cend;
+      if (!cleaner_shutdown && now - curl->lastuse < std::chrono::seconds(MAXIDLE))
+        break;
+      saved_curl.erase(cend);
+      release_curl_handle_now(curl);
+    }
+  }
+  return nullptr;
+}
+
+void RGWCurlHandles::stop()
+{
+  Mutex::Locker lock(cleaner_lock);
+  cleaner_shutdown = 1;
+  cleaner_cond.Signal();
+}
+
+void RGWCurlHandles::flush_curl_handles()
+{
+  stop();
+  join();
+  if (!saved_curl.empty()) {
+    dout(0) << "ERROR: " << __func__ << " failed final cleanup" << dendl;
+  }
+  saved_curl.shrink_to_fit();
+}
+
+CURL *rgw_http_req_data::get_easy_handle() const
+{
+  return **curl_handle;
+}
+
+static RGWCurlHandles *handles;
+
+static RGWCurlHandle *do_curl_easy_init()
+{
+  return handles->get_curl_handle();
+}
+
+static void do_curl_easy_cleanup(RGWCurlHandle *curl_handle)
+{
+  handles->release_curl_handle(curl_handle);
+}
+
+// XXX make this part of the token cache?  (but that's swift-only;
+//	and this especially needs to integrates with s3...)
+
+void rgw_setup_saved_curl_handles()
+{
+  handles = new RGWCurlHandles();
+  handles->create("rgw_curl");
+}
+
+void rgw_release_all_curl_handles()
+{
+  handles->flush_curl_handles();
+  delete handles;
+}
+
+void RGWIOProvider::assign_io(RGWIOIDProvider& io_id_provider, int io_type)
+{
+  if (id == 0) {
+    id = io_id_provider.get_next();
+  }
+}
+
+/*
+ * the following set of callbacks will be called either on RGWHTTPManager::process(),
+ * or via the RGWHTTPManager async processing.
+ */
+size_t RGWHTTPClient::receive_http_header(void * const ptr,
+                                          const size_t size,
+                                          const size_t nmemb,
+                                          void * const _info)
+{
+  rgw_http_req_data *req_data = static_cast<rgw_http_req_data *>(_info);
+  size_t len = size * nmemb;
+
+  Mutex::Locker l(req_data->lock);
+  
+  if (!req_data->registered) {
+    return len;
+  }
+
+  int ret = req_data->client->receive_header(ptr, size * nmemb);
+  if (ret < 0) {
+    dout(0) << "WARNING: client->receive_header() returned ret=" << ret << dendl;
+  }
+
+  return len;
+}
+
+size_t RGWHTTPClient::receive_http_data(void * const ptr,
+                                        const size_t size,
+                                        const size_t nmemb,
+                                        void * const _info)
+{
+  rgw_http_req_data *req_data = static_cast<rgw_http_req_data *>(_info);
+  size_t len = size * nmemb;
+
+  bool pause = false;
+
+  RGWHTTPClient *client;
+
+  {
+    Mutex::Locker l(req_data->lock);
+    if (!req_data->registered) {
+      return len;
+    }
+
+    client = req_data->client;
+  }
+
+  size_t& skip_bytes = client->receive_pause_skip;
+
+  if (skip_bytes >= len) {
+    skip_bytes -= len;
+    return len;
+  }
+
+  int ret = client->receive_data((char *)ptr + skip_bytes, len - skip_bytes, &pause);
+  if (ret < 0) {
+    dout(0) << "WARNING: client->receive_data() returned ret=" << ret << dendl;
+  }
+
+  if (pause) {
+    dout(20) << "RGWHTTPClient::receive_http_data(): pause" << dendl;
+    skip_bytes = len;
+    Mutex::Locker l(req_data->lock);
+    req_data->read_paused = true;
+    return CURL_WRITEFUNC_PAUSE;
+  }
+
+  skip_bytes = 0;
+
+  return len;
+}
+
+size_t RGWHTTPClient::send_http_data(void * const ptr,
+                                     const size_t size,
+                                     const size_t nmemb,
+                                     void * const _info)
+{
+  rgw_http_req_data *req_data = static_cast<rgw_http_req_data *>(_info);
+
+  RGWHTTPClient *client;
+
+  {
+    Mutex::Locker l(req_data->lock);
+  
+    if (!req_data->registered) {
+      return 0;
+    }
+
+    client = req_data->client;
+  }
+
+  bool pause = false;
+
+  int ret = client->send_data(ptr, size * nmemb, &pause);
+  if (ret < 0) {
+    dout(0) << "WARNING: client->receive_data() returned ret=" << ret << dendl;
+  }
+
+  if (ret == 0 &&
+      pause) {
+    Mutex::Locker l(req_data->lock);
+    req_data->write_paused = true;
+    return CURL_READFUNC_PAUSE;
+  }
+
+  return ret;
+}
+
+Mutex& RGWHTTPClient::get_req_lock()
+{
+  return req_data->lock;
+}
+
+void RGWHTTPClient::_set_write_paused(bool pause)
+{
+  ceph_assert(req_data->lock.is_locked());
+  
+  RGWHTTPManager *mgr = req_data->mgr;
+  if (pause == req_data->write_paused) {
+    return;
+  }
+  if (pause) {
+    mgr->set_request_state(this, SET_WRITE_PAUSED);
+  } else {
+    mgr->set_request_state(this, SET_WRITE_RESUME);
+  }
+}
+
+void RGWHTTPClient::_set_read_paused(bool pause)
+{
+  ceph_assert(req_data->lock.is_locked());
+  
+  RGWHTTPManager *mgr = req_data->mgr;
+  if (pause == req_data->read_paused) {
+    return;
+  }
+  if (pause) {
+    mgr->set_request_state(this, SET_READ_PAUSED);
+  } else {
+    mgr->set_request_state(this, SET_READ_RESUME);
+  }
+}
+
+static curl_slist *headers_to_slist(param_vec_t& headers)
+{
+  curl_slist *h = NULL;
+
+  param_vec_t::iterator iter;
+  for (iter = headers.begin(); iter != headers.end(); ++iter) {
+    pair<string, string>& p = *iter;
+    string val = p.first;
+
+    if (strncmp(val.c_str(), "HTTP_", 5) == 0) {
+      val = val.substr(5);
+    }
+
+    /* we need to convert all underscores into dashes as some web servers forbid them
+     * in the http header field names
+     */
+    for (size_t i = 0; i < val.size(); i++) {
+      if (val[i] == '_') {
+        val[i] = '-';
+      }
+    }
+    
+    val = camelcase_dash_http_attr(val);
+
+    // curl won't send headers with empty values unless it ends with a ; instead
+    if (p.second.empty()) {
+      val.append(1, ';');
+    } else {
+      val.append(": ");
+      val.append(p.second);
+    }
+    h = curl_slist_append(h, val.c_str());
+  }
+
+  return h;
+}
+
+static bool is_upload_request(const string& method)
+{
+  return method == "POST" || method == "PUT";
+}
+
+/*
+ * process a single simple one off request
+ */
+int RGWHTTPClient::process(optional_yield y)
+{
+  return RGWHTTP::process(this, y);
+}
+
+string RGWHTTPClient::to_str()
+{
+  string method_str = (method.empty() ? "<no-method>" : method);
+  string url_str = (url.empty() ? "<no-url>" : url);
+  return method_str + " " + url_str;
+}
+
+int RGWHTTPClient::get_req_retcode()
+{
+  if (!req_data) {
+    return -EINVAL;
+  }
+
+  return req_data->get_retcode();
+}
+
+/*
+ * init request, will be used later with RGWHTTPManager
+ */
+int RGWHTTPClient::init_request(rgw_http_req_data *_req_data)
+{
+  ceph_assert(!req_data);
+  _req_data->get();
+  req_data = _req_data;
+
+  req_data->curl_handle = do_curl_easy_init();
+
+  CURL *easy_handle = req_data->get_easy_handle();
+
+  dout(20) << "sending request to " << url << dendl;
+
+  curl_slist *h = headers_to_slist(headers);
+
+  req_data->h = h;
+
+  curl_easy_setopt(easy_handle, CURLOPT_CUSTOMREQUEST, method.c_str());
+  curl_easy_setopt(easy_handle, CURLOPT_URL, url.c_str());
+  curl_easy_setopt(easy_handle, CURLOPT_NOPROGRESS, 1L);
+  curl_easy_setopt(easy_handle, CURLOPT_NOSIGNAL, 1L);
+  curl_easy_setopt(easy_handle, CURLOPT_HEADERFUNCTION, receive_http_header);
+  curl_easy_setopt(easy_handle, CURLOPT_WRITEHEADER, (void *)req_data);
+  curl_easy_setopt(easy_handle, CURLOPT_WRITEFUNCTION, receive_http_data);
+  curl_easy_setopt(easy_handle, CURLOPT_WRITEDATA, (void *)req_data);
+  curl_easy_setopt(easy_handle, CURLOPT_ERRORBUFFER, (void *)req_data->error_buf);
+  curl_easy_setopt(easy_handle, CURLOPT_LOW_SPEED_TIME, cct->_conf->rgw_curl_low_speed_time);
+  curl_easy_setopt(easy_handle, CURLOPT_LOW_SPEED_LIMIT, cct->_conf->rgw_curl_low_speed_limit);
+  if (h) {
+    curl_easy_setopt(easy_handle, CURLOPT_HTTPHEADER, (void *)h);
+  }
+  curl_easy_setopt(easy_handle, CURLOPT_READFUNCTION, send_http_data);
+  curl_easy_setopt(easy_handle, CURLOPT_READDATA, (void *)req_data);
+  if (send_data_hint || is_upload_request(method)) {
+    curl_easy_setopt(easy_handle, CURLOPT_UPLOAD, 1L);
+  }
+  if (has_send_len) {
+    curl_easy_setopt(easy_handle, CURLOPT_INFILESIZE, (void *)send_len); 
+  }
+  if (!verify_ssl) {
+    curl_easy_setopt(easy_handle, CURLOPT_SSL_VERIFYPEER, 0L);
+    curl_easy_setopt(easy_handle, CURLOPT_SSL_VERIFYHOST, 0L);
+    dout(20) << "ssl verification is set to off" << dendl;
+  }
+  curl_easy_setopt(easy_handle, CURLOPT_PRIVATE, (void *)req_data);
+
+  return 0;
+}
+
+bool RGWHTTPClient::is_done()
+{
+  return req_data->is_done();
+}
+
+/*
+ * wait for async request to complete
+ */
+int RGWHTTPClient::wait(optional_yield y)
+{
+  return req_data->wait(y);
+}
+
+void RGWHTTPClient::cancel()
+{
+  if (req_data) {
+    RGWHTTPManager *http_manager = req_data->mgr;
+    if (http_manager) {
+      http_manager->remove_request(this);
+    }
+  }
+}
+
+RGWHTTPClient::~RGWHTTPClient()
+{
+  cancel();
+  if (req_data) {
+    req_data->put();
+  }
+}
+
+
+int RGWHTTPHeadersCollector::receive_header(void * const ptr, const size_t len)
+{
+  const boost::string_ref header_line(static_cast<const char *>(ptr), len);
+
+  /* We're tokening the line that way due to backward compatibility. */
+  const size_t sep_loc = header_line.find_first_of(" \t:");
+
+  if (boost::string_ref::npos == sep_loc) {
+    /* Wrongly formatted header? Just skip it. */
+    return 0;
+  }
+
+  header_name_t name(header_line.substr(0, sep_loc));
+  if (0 == relevant_headers.count(name)) {
+    /* Not interested in this particular header. */
+    return 0;
+  }
+
+  const auto value_part = header_line.substr(sep_loc + 1);
+
+  /* Skip spaces and tabs after the separator. */
+  const size_t val_loc_s = value_part.find_first_not_of(' ');
+  const size_t val_loc_e = value_part.find_first_of("\r\n");
+
+  if (boost::string_ref::npos == val_loc_s ||
+      boost::string_ref::npos == val_loc_e) {
+    /* Empty value case. */
+    found_headers.emplace(name, header_value_t());
+  } else {
+    found_headers.emplace(name, header_value_t(
+        value_part.substr(val_loc_s, val_loc_e - val_loc_s)));
+  }
+
+  return 0;
+}
+
+int RGWHTTPTransceiver::send_data(void* ptr, size_t len, bool* pause)
+{
+  int length_to_copy = 0;
+  if (post_data_index < post_data.length()) {
+    length_to_copy = min(post_data.length() - post_data_index, len);
+    memcpy(ptr, post_data.data() + post_data_index, length_to_copy);
+    post_data_index += length_to_copy;
+  }
+  return length_to_copy;
+}
+
+
+static int clear_signal(int fd)
+{
+  // since we're in non-blocking mode, we can try to read a lot more than
+  // one signal from signal_thread() to avoid later wakeups. non-blocking reads
+  // are also required to support the curl_multi_wait bug workaround
+  std::array<char, 256> buf;
+  int ret = ::read(fd, (void *)buf.data(), buf.size());
+  if (ret < 0) {
+    ret = -errno;
+    return ret == -EAGAIN ? 0 : ret; // clear EAGAIN
+  }
+  return 0;
+}
+
+#if HAVE_CURL_MULTI_WAIT
+
+static std::once_flag detect_flag;
+static bool curl_multi_wait_bug_present = false;
+
+static int detect_curl_multi_wait_bug(CephContext *cct, CURLM *handle,
+                                      int write_fd, int read_fd)
+{
+  int ret = 0;
+
+  // write to write_fd so that read_fd becomes readable
+  uint32_t buf = 0;
+  ret = ::write(write_fd, &buf, sizeof(buf));
+  if (ret < 0) {
+    ret = -errno;
+    ldout(cct, 0) << "ERROR: " << __func__ << "(): write() returned " << ret << dendl;
+    return ret;
+  }
+
+  // pass read_fd in extra_fds for curl_multi_wait()
+  int num_fds;
+  struct curl_waitfd wait_fd;
+
+  wait_fd.fd = read_fd;
+  wait_fd.events = CURL_WAIT_POLLIN;
+  wait_fd.revents = 0;
+
+  ret = curl_multi_wait(handle, &wait_fd, 1, 0, &num_fds);
+  if (ret != CURLM_OK) {
+    ldout(cct, 0) << "ERROR: curl_multi_wait() returned " << ret << dendl;
+    return -EIO;
+  }
+
+  // curl_multi_wait should flag revents when extra_fd is readable. if it
+  // doesn't, the bug is present and we can't rely on revents
+  if (wait_fd.revents == 0) {
+    curl_multi_wait_bug_present = true;
+    ldout(cct, 0) << "WARNING: detected a version of libcurl which contains a "
+        "bug in curl_multi_wait(). enabling a workaround that may degrade "
+        "performance slightly." << dendl;
+  }
+
+  return clear_signal(read_fd);
+}
+
+static bool is_signaled(const curl_waitfd& wait_fd)
+{
+  if (wait_fd.fd < 0) {
+    // no fd to signal
+    return false;
+  }
+
+  if (curl_multi_wait_bug_present) {
+    // we can't rely on revents, so we always return true if a wait_fd is given.
+    // this means we'll be trying a non-blocking read on this fd every time that
+    // curl_multi_wait() wakes up
+    return true;
+  }
+
+  return wait_fd.revents > 0;
+}
+
+static int do_curl_wait(CephContext *cct, CURLM *handle, int signal_fd)
+{
+  int num_fds;
+  struct curl_waitfd wait_fd;
+
+  wait_fd.fd = signal_fd;
+  wait_fd.events = CURL_WAIT_POLLIN;
+  wait_fd.revents = 0;
+
+  int ret = curl_multi_wait(handle, &wait_fd, 1, cct->_conf->rgw_curl_wait_timeout_ms, &num_fds);
+  if (ret) {
+    ldout(cct, 0) << "ERROR: curl_multi_wait() returned " << ret << dendl;
+    return -EIO;
+  }
+
+  if (is_signaled(wait_fd)) {
+    ret = clear_signal(signal_fd);
+    if (ret < 0) {
+      ldout(cct, 0) << "ERROR: " << __func__ << "(): read() returned " << ret << dendl;
+      return ret;
+    }
+  }
+  return 0;
+}
+
+#else
+
+static int do_curl_wait(CephContext *cct, CURLM *handle, int signal_fd)
+{
+  fd_set fdread;
+  fd_set fdwrite;
+  fd_set fdexcep;
+  int maxfd = -1;
+ 
+  FD_ZERO(&fdread);
+  FD_ZERO(&fdwrite);
+  FD_ZERO(&fdexcep);
+
+  /* get file descriptors from the transfers */ 
+  int ret = curl_multi_fdset(handle, &fdread, &fdwrite, &fdexcep, &maxfd);
+  if (ret) {
+    ldout(cct, 0) << "ERROR: curl_multi_fdset returned " << ret << dendl;
+    return -EIO;
+  }
+
+  if (signal_fd > 0) {
+    FD_SET(signal_fd, &fdread);
+    if (signal_fd >= maxfd) {
+      maxfd = signal_fd + 1;
+    }
+  }
+
+  /* forcing a strict timeout, as the returned fdsets might not reference all fds we wait on */
+  uint64_t to = cct->_conf->rgw_curl_wait_timeout_ms;
+#define RGW_CURL_TIMEOUT 1000
+  if (!to)
+    to = RGW_CURL_TIMEOUT;
+  struct timeval timeout;
+  timeout.tv_sec = to / 1000;
+  timeout.tv_usec = to % 1000;
+
+  ret = select(maxfd+1, &fdread, &fdwrite, &fdexcep, &timeout);
+  if (ret < 0) {
+    ret = -errno;
+    ldout(cct, 0) << "ERROR: select returned " << ret << dendl;
+    return ret;
+  }
+
+  if (signal_fd > 0 && FD_ISSET(signal_fd, &fdread)) {
+    ret = clear_signal(signal_fd);
+    if (ret < 0) {
+      ldout(cct, 0) << "ERROR: " << __func__ << "(): read() returned " << ret << dendl;
+      return ret;
+    }
+  }
+
+  return 0;
+}
+
+#endif
+
+void *RGWHTTPManager::ReqsThread::entry()
+{
+  manager->reqs_thread_entry();
+  return NULL;
+}
+
+/*
+ * RGWHTTPManager has two modes of operation: threaded and non-threaded.
+ */
+RGWHTTPManager::RGWHTTPManager(CephContext *_cct, RGWCompletionManager *_cm) : cct(_cct),
+                                                    completion_mgr(_cm), is_started(false),
+                                                    reqs_lock("RGWHTTPManager::reqs_lock"), num_reqs(0), max_threaded_req(0),
+                                                    reqs_thread(NULL)
+{
+  multi_handle = (void *)curl_multi_init();
+  thread_pipe[0] = -1;
+  thread_pipe[1] = -1;
+}
+
+RGWHTTPManager::~RGWHTTPManager() {
+  stop();
+  if (multi_handle)
+    curl_multi_cleanup((CURLM *)multi_handle);
+}
+
+void RGWHTTPManager::register_request(rgw_http_req_data *req_data)
+{
+  RWLock::WLocker rl(reqs_lock);
+  req_data->id = num_reqs;
+  req_data->registered = true;
+  reqs[num_reqs] = req_data;
+  num_reqs++;
+  ldout(cct, 20) << __func__ << " mgr=" << this << " req_data->id=" << req_data->id << ", curl_handle=" << req_data->curl_handle << dendl;
+}
+
+bool RGWHTTPManager::unregister_request(rgw_http_req_data *req_data)
+{
+  RWLock::WLocker rl(reqs_lock);
+  if (!req_data->registered) {
+    return false;
+  }
+  req_data->get();
+  req_data->registered = false;
+  unregistered_reqs.push_back(req_data);
+  ldout(cct, 20) << __func__ << " mgr=" << this << " req_data->id=" << req_data->id << ", curl_handle=" << req_data->curl_handle << dendl;
+  return true;
+}
+
+void RGWHTTPManager::complete_request(rgw_http_req_data *req_data)
+{
+  RWLock::WLocker rl(reqs_lock);
+  _complete_request(req_data);
+}
+
+void RGWHTTPManager::_complete_request(rgw_http_req_data *req_data)
+{
+  map<uint64_t, rgw_http_req_data *>::iterator iter = reqs.find(req_data->id);
+  if (iter != reqs.end()) {
+    reqs.erase(iter);
+  }
+  {
+    Mutex::Locker l(req_data->lock);
+    req_data->mgr = nullptr;
+  }
+  if (completion_mgr) {
+    completion_mgr->complete(NULL, req_data->control_io_id, req_data->user_info);
+  }
+
+  req_data->put();
+}
+
+void RGWHTTPManager::finish_request(rgw_http_req_data *req_data, int ret, long http_status)
+{
+  req_data->finish(ret, http_status);
+  complete_request(req_data);
+}
+
+void RGWHTTPManager::_finish_request(rgw_http_req_data *req_data, int ret)
+{
+  req_data->finish(ret);
+  _complete_request(req_data);
+}
+
+void RGWHTTPManager::_set_req_state(set_state& ss)
+{
+  ss.req->set_state(ss.bitmask);
+}
+/*
+ * hook request to the curl multi handle
+ */
+int RGWHTTPManager::link_request(rgw_http_req_data *req_data)
+{
+  ldout(cct, 20) << __func__ << " req_data=" << req_data << " req_data->id=" << req_data->id << ", curl_handle=" << req_data->curl_handle << dendl;
+  CURLMcode mstatus = curl_multi_add_handle((CURLM *)multi_handle, req_data->get_easy_handle());
+  if (mstatus) {
+    dout(0) << "ERROR: failed on curl_multi_add_handle, status=" << mstatus << dendl;
+    return -EIO;
+  }
+  return 0;
+}
+
+/*
+ * unhook request from the curl multi handle, and finish request if it wasn't finished yet as
+ * there will be no more processing on this request
+ */
+void RGWHTTPManager::_unlink_request(rgw_http_req_data *req_data)
+{
+  if (req_data->curl_handle) {
+    curl_multi_remove_handle((CURLM *)multi_handle, req_data->get_easy_handle());
+  }
+  if (!req_data->is_done()) {
+    _finish_request(req_data, -ECANCELED);
+  }
+}
+
+void RGWHTTPManager::unlink_request(rgw_http_req_data *req_data)
+{
+  RWLock::WLocker wl(reqs_lock);
+  _unlink_request(req_data);
+}
+
+void RGWHTTPManager::manage_pending_requests()
+{
+  reqs_lock.get_read();
+  if (max_threaded_req == num_reqs &&
+      unregistered_reqs.empty() &&
+      reqs_change_state.empty()) {
+    reqs_lock.unlock();
+    return;
+  }
+  reqs_lock.unlock();
+
+  RWLock::WLocker wl(reqs_lock);
+
+  if (!reqs_change_state.empty()) {
+    for (auto siter : reqs_change_state) {
+      _set_req_state(siter);
+    }
+    reqs_change_state.clear();
+  }
+
+  if (!unregistered_reqs.empty()) {
+    for (auto& r : unregistered_reqs) {
+      _unlink_request(r);
+      r->put();
+    }
+
+    unregistered_reqs.clear();
+  }
+
+  map<uint64_t, rgw_http_req_data *>::iterator iter = reqs.find(max_threaded_req);
+
+  list<std::pair<rgw_http_req_data *, int> > remove_reqs;
+
+  for (; iter != reqs.end(); ++iter) {
+    rgw_http_req_data *req_data = iter->second;
+    int r = link_request(req_data);
+    if (r < 0) {
+      ldout(cct, 0) << "ERROR: failed to link http request" << dendl;
+      remove_reqs.push_back(std::make_pair(iter->second, r));
+    } else {
+      max_threaded_req = iter->first + 1;
+    }
+  }
+
+  for (auto piter : remove_reqs) {
+    rgw_http_req_data *req_data = piter.first;
+    int r = piter.second;
+
+    _finish_request(req_data, r);
+  }
+}
+
+int RGWHTTPManager::add_request(RGWHTTPClient *client)
+{
+  rgw_http_req_data *req_data = new rgw_http_req_data;
+
+  int ret = client->init_request(req_data);
+  if (ret < 0) {
+    req_data->put();
+    req_data = NULL;
+    return ret;
+  }
+
+  req_data->mgr = this;
+  req_data->client = client;
+  req_data->control_io_id = client->get_io_id(RGWHTTPClient::HTTPCLIENT_IO_CONTROL);
+  req_data->user_info = client->get_io_user_info();
+
+  register_request(req_data);
+
+  if (!is_started) {
+    ret = link_request(req_data);
+    if (ret < 0) {
+      req_data->put();
+      req_data = NULL;
+    }
+    return ret;
+  }
+  ret = signal_thread();
+  if (ret < 0) {
+    finish_request(req_data, ret);
+  }
+
+  return ret;
+}
+
+int RGWHTTPManager::remove_request(RGWHTTPClient *client)
+{
+  rgw_http_req_data *req_data = client->get_req_data();
+
+  if (!is_started) {
+    unlink_request(req_data);
+    return 0;
+  }
+  if (!unregister_request(req_data)) {
+    return 0;
+  }
+  int ret = signal_thread();
+  if (ret < 0) {
+    return ret;
+  }
+
+  return 0;
+}
+
+int RGWHTTPManager::set_request_state(RGWHTTPClient *client, RGWHTTPRequestSetState state)
+{
+  rgw_http_req_data *req_data = client->get_req_data();
+
+  ceph_assert(req_data->lock.is_locked());
+
+  /* can only do that if threaded */
+  if (!is_started) {
+    return -EINVAL;
+  }
+
+  bool suggested_wr_paused = req_data->write_paused;
+  bool suggested_rd_paused = req_data->read_paused;
+
+  switch (state) {
+    case SET_WRITE_PAUSED:
+      suggested_wr_paused = true;
+      break;
+    case SET_WRITE_RESUME:
+      suggested_wr_paused = false;
+      break;
+    case SET_READ_PAUSED:
+      suggested_rd_paused = true;
+      break;
+    case SET_READ_RESUME:
+      suggested_rd_paused = false;
+      break;
+    default:
+      /* shouldn't really be here */
+      return -EIO;
+  }
+  if (suggested_wr_paused == req_data->write_paused &&
+      suggested_rd_paused == req_data->read_paused) {
+    return 0;
+  }
+
+  req_data->write_paused = suggested_wr_paused;
+  req_data->read_paused = suggested_rd_paused;
+
+  int bitmask = CURLPAUSE_CONT;
+
+  if (req_data->write_paused) {
+    bitmask |= CURLPAUSE_SEND;
+  }
+
+  if (req_data->read_paused) {
+    bitmask |= CURLPAUSE_RECV;
+  }
+
+  reqs_change_state.push_back(set_state(req_data, bitmask));
+  int ret = signal_thread();
+  if (ret < 0) {
+    return ret;
+  }
+
+  return 0;
+}
+
+int RGWHTTPManager::start()
+{
+  if (pipe_cloexec(thread_pipe) < 0) {
+    int e = errno;
+    ldout(cct, 0) << "ERROR: pipe(): " << cpp_strerror(e) << dendl;
+    return -e;
+  }
+
+  // enable non-blocking reads
+  if (::fcntl(thread_pipe[0], F_SETFL, O_NONBLOCK) < 0) {
+    int e = errno;
+    ldout(cct, 0) << "ERROR: fcntl(): " << cpp_strerror(e) << dendl;
+    TEMP_FAILURE_RETRY(::close(thread_pipe[0]));
+    TEMP_FAILURE_RETRY(::close(thread_pipe[1]));
+    return -e;
+  }
+
+#ifdef HAVE_CURL_MULTI_WAIT
+  // on first initialization, use this pipe to detect whether we're using a
+  // buggy version of libcurl
+  std::call_once(detect_flag, detect_curl_multi_wait_bug, cct,
+                 static_cast<CURLM*>(multi_handle),
+                 thread_pipe[1], thread_pipe[0]);
+#endif
+
+  is_started = true;
+  reqs_thread = new ReqsThread(this);
+  reqs_thread->create("http_manager");
+  return 0;
+}
+
+void RGWHTTPManager::stop()
+{
+  if (is_stopped) {
+    return;
+  }
+
+  is_stopped = true;
+
+  if (is_started) {
+    going_down = true;
+    signal_thread();
+    reqs_thread->join();
+    delete reqs_thread;
+    TEMP_FAILURE_RETRY(::close(thread_pipe[1]));
+    TEMP_FAILURE_RETRY(::close(thread_pipe[0]));
+  }
+}
+
+int RGWHTTPManager::signal_thread()
+{
+  uint32_t buf = 0;
+  int ret = write(thread_pipe[1], (void *)&buf, sizeof(buf));
+  if (ret < 0) {
+    ret = -errno;
+    ldout(cct, 0) << "ERROR: " << __func__ << ": write() returned ret=" << ret << dendl;
+    return ret;
+  }
+  return 0;
+}
+
+void *RGWHTTPManager::reqs_thread_entry()
+{
+  int still_running;
+  int mstatus;
+
+  ldout(cct, 20) << __func__ << ": start" << dendl;
+
+  while (!going_down) {
+    int ret = do_curl_wait(cct, (CURLM *)multi_handle, thread_pipe[0]);
+    if (ret < 0) {
+      dout(0) << "ERROR: do_curl_wait() returned: " << ret << dendl;
+      return NULL;
+    }
+
+    manage_pending_requests();
+
+    mstatus = curl_multi_perform((CURLM *)multi_handle, &still_running);
+    switch (mstatus) {
+      case CURLM_OK:
+      case CURLM_CALL_MULTI_PERFORM:
+        break;
+      default:
+        dout(10) << "curl_multi_perform returned: " << mstatus << dendl;
+	break;
+    }
+    int msgs_left;
+    CURLMsg *msg;
+    while ((msg = curl_multi_info_read((CURLM *)multi_handle, &msgs_left))) {
+      if (msg->msg == CURLMSG_DONE) {
+	int result = msg->data.result;
+	CURL *e = msg->easy_handle;
+	rgw_http_req_data *req_data;
+	curl_easy_getinfo(e, CURLINFO_PRIVATE, (void **)&req_data);
+	curl_multi_remove_handle((CURLM *)multi_handle, e);
+
+	long http_status;
+	curl_easy_getinfo(e, CURLINFO_RESPONSE_CODE, (void **)&http_status);
+
+	int status = rgw_http_error_to_errno(http_status);
+        if (result != CURLE_OK && status == 0) {
+          dout(0) << "ERROR: curl error: " << curl_easy_strerror((CURLcode)result) << ", maybe network unstable" << dendl;
+          status = -EAGAIN;
+        }
+        int id = req_data->id;
+	finish_request(req_data, status, http_status);
+        switch (result) {
+          case CURLE_OK:
+            break;
+          case CURLE_OPERATION_TIMEDOUT:
+            dout(0) << "WARNING: curl operation timed out, network average transfer speed less than " 
+              << cct->_conf->rgw_curl_low_speed_limit << " Bytes per second during " << cct->_conf->rgw_curl_low_speed_time << " seconds." << dendl;
+          default:
+            dout(20) << "ERROR: msg->data.result=" << result << " req_data->id=" << id << " http_status=" << http_status << dendl;
+            dout(20) << "ERROR: curl error: " << curl_easy_strerror((CURLcode)result) << dendl;
+	    break;
+        }
+      }
+    }
+  }
+
+
+  RWLock::WLocker rl(reqs_lock);
+  for (auto r : unregistered_reqs) {
+    _unlink_request(r);
+  }
+
+  unregistered_reqs.clear();
+
+  auto all_reqs = std::move(reqs);
+  for (auto iter : all_reqs) {
+    _unlink_request(iter.second);
+  }
+
+  reqs.clear();
+
+  if (completion_mgr) {
+    completion_mgr->go_down();
+  }
+  
+  return 0;
+}
+
+void rgw_http_client_init(CephContext *cct)
+{
+  curl_global_init(CURL_GLOBAL_ALL);
+  rgw_http_manager = new RGWHTTPManager(cct);
+  rgw_http_manager->start();
+}
+
+void rgw_http_client_cleanup()
+{
+  rgw_http_manager->stop();
+  delete rgw_http_manager;
+  curl_global_cleanup();
+}
+
+
+int RGWHTTP::send(RGWHTTPClient *req) {
+  if (!req) {
+    return 0;
+  }
+  int r = rgw_http_manager->add_request(req);
+  if (r < 0) {
+    return r;
+  }
+
+  return 0;
+}
+
+int RGWHTTP::process(RGWHTTPClient *req, optional_yield y) {
+  if (!req) {
+    return 0;
+  }
+  int r = send(req);
+  if (r < 0) {
+    return r;
+  }
+
+  return req->wait(y);
+}
+