src/httpfetch.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "httpfetch.h"
  21 #include "porting.h" // for sleep_ms(), get_sysinfo(), secure_rand_fill_buf()
  22 #include <iostream>
  23 #include <sstream>
  24 #include <list>
  25 #include <map>
  26 #include <cerrno>
  27 #include <mutex>
  28 #include "network/socket.h" // for select()
  29 #include "threading/event.h"
  30 #include "config.h"
  31 #include "exceptions.h"
  32 #include "debug.h"
  33 #include "log.h"
  34 #include "util/container.h"
  35 #include "util/thread.h"
  36 #include "version.h"
  37 #include "settings.h"
  38 #include "noise.h"
  39
  40 std::mutex g_httpfetch_mutex;
  41 std::map<unsigned long, std::queue<HTTPFetchResult> > g_httpfetch_results;
  42 PcgRandom g_callerid_randomness;
  43
  44 HTTPFetchRequest::HTTPFetchRequest() :
  45         timeout(g_settings->getS32("curl_timeout")),
  46         connect_timeout(timeout),
  47         useragent(std::string(PROJECT_NAME_C "/") + g_version_hash + " (" + porting::get_sysinfo() + ")")
  48 {
  49 }
  50
  51
  52 static void httpfetch_deliver_result(const HTTPFetchResult &fetch_result)
  53 {
  54         unsigned long caller = fetch_result.caller;
  55         if (caller != HTTPFETCH_DISCARD) {
  56                 MutexAutoLock lock(g_httpfetch_mutex);
  57                 g_httpfetch_results[caller].push(fetch_result);
  58         }
  59 }
  60
  61 static void httpfetch_request_clear(unsigned long caller);
  62
  63 unsigned long httpfetch_caller_alloc()
  64 {
  65         MutexAutoLock lock(g_httpfetch_mutex);
  66
  67         // Check each caller ID except HTTPFETCH_DISCARD
  68         const unsigned long discard = HTTPFETCH_DISCARD;
  69         for (unsigned long caller = discard + 1; caller != discard; ++caller) {
  70                 std::map<unsigned long, std::queue<HTTPFetchResult> >::iterator
  71                         it = g_httpfetch_results.find(caller);
  72                 if (it == g_httpfetch_results.end()) {
  73                         verbosestream << "httpfetch_caller_alloc: allocating "
  74                                         << caller << std::endl;
  75                         // Access element to create it
  76                         g_httpfetch_results[caller];
  77                         return caller;
  78                 }
  79         }
  80
  81         FATAL_ERROR("httpfetch_caller_alloc: ran out of caller IDs");
  82         return discard;
  83 }
  84
  85 unsigned long httpfetch_caller_alloc_secure()
  86 {
  87         MutexAutoLock lock(g_httpfetch_mutex);
  88
  89         // Generate random caller IDs and make sure they're not
  90         // already used or equal to HTTPFETCH_DISCARD
  91         // Give up after 100 tries to prevent infinite loop
  92         u8 tries = 100;
  93         unsigned long caller;
  94
  95         do {
  96                 caller = (((u64) g_callerid_randomness.next()) << 32) |
  97                                 g_callerid_randomness.next();
  98
  99                 if (--tries < 1) {
 100                         FATAL_ERROR("httpfetch_caller_alloc_secure: ran out of caller IDs");
 101                         return HTTPFETCH_DISCARD;
 102                 }
 103         } while (g_httpfetch_results.find(caller) != g_httpfetch_results.end());
 104
 105         verbosestream << "httpfetch_caller_alloc_secure: allocating "
 106                 << caller << std::endl;
 107
 108         // Access element to create it
 109         g_httpfetch_results[caller];
 110         return caller;
 111 }
 112
 113 void httpfetch_caller_free(unsigned long caller)
 114 {
 115         verbosestream<<"httpfetch_caller_free: freeing "
 116                         <<caller<<std::endl;
 117
 118         httpfetch_request_clear(caller);
 119         if (caller != HTTPFETCH_DISCARD) {
 120                 MutexAutoLock lock(g_httpfetch_mutex);
 121                 g_httpfetch_results.erase(caller);
 122         }
 123 }
 124
 125 bool httpfetch_async_get(unsigned long caller, HTTPFetchResult &fetch_result)
 126 {
 127         MutexAutoLock lock(g_httpfetch_mutex);
 128
 129         // Check that caller exists
 130         std::map<unsigned long, std::queue<HTTPFetchResult> >::iterator
 131                 it = g_httpfetch_results.find(caller);
 132         if (it == g_httpfetch_results.end())
 133                 return false;
 134
 135         // Check that result queue is nonempty
 136         std::queue<HTTPFetchResult> &caller_results = it->second;
 137         if (caller_results.empty())
 138                 return false;
 139
 140         // Pop first result
 141         fetch_result = caller_results.front();
 142         caller_results.pop();
 143         return true;
 144 }
 145
 146 #if USE_CURL
 147 #include <curl/curl.h>
 148
 149 /*
 150         USE_CURL is on: use cURL based httpfetch implementation
 151 */
 152
 153 static size_t httpfetch_writefunction(
 154                 char *ptr, size_t size, size_t nmemb, void *userdata)
 155 {
 156         std::ostringstream *stream = (std::ostringstream*)userdata;
 157         size_t count = size * nmemb;
 158         stream->write(ptr, count);
 159         return count;
 160 }
 161
 162 static size_t httpfetch_discardfunction(
 163                 char *ptr, size_t size, size_t nmemb, void *userdata)
 164 {
 165         return size * nmemb;
 166 }
 167
 168 class CurlHandlePool
 169 {
 170         std::list<CURL*> handles;
 171
 172 public:
 173         CurlHandlePool() = default;
 174
 175         ~CurlHandlePool()
 176         {
 177                 for (std::list<CURL*>::iterator it = handles.begin();
 178                                 it != handles.end(); ++it) {
 179                         curl_easy_cleanup(*it);
 180                 }
 181         }
 182         CURL * alloc()
 183         {
 184                 CURL *curl;
 185                 if (handles.empty()) {
 186                         curl = curl_easy_init();
 187                         if (curl == NULL) {
 188                                 errorstream<<"curl_easy_init returned NULL"<<std::endl;
 189                         }
 190                 }
 191                 else {
 192                         curl = handles.front();
 193                         handles.pop_front();
 194                 }
 195                 return curl;
 196         }
 197         void free(CURL *handle)
 198         {
 199                 if (handle)
 200                         handles.push_back(handle);
 201         }
 202 };
 203
 204 class HTTPFetchOngoing
 205 {
 206 public:
 207         HTTPFetchOngoing(const HTTPFetchRequest &request, CurlHandlePool *pool);
 208         ~HTTPFetchOngoing();
 209
 210         CURLcode start(CURLM *multi);
 211         const HTTPFetchResult * complete(CURLcode res);
 212
 213         const HTTPFetchRequest &getRequest()    const { return request; };
 214         const CURL             *getEasyHandle() const { return curl; };
 215
 216 private:
 217         CurlHandlePool *pool;
 218         CURL *curl;
 219         CURLM *multi;
 220         HTTPFetchRequest request;
 221         HTTPFetchResult result;
 222         std::ostringstream oss;
 223         struct curl_slist *http_header;
 224         curl_httppost *post;
 225 };
 226
 227
 228 HTTPFetchOngoing::HTTPFetchOngoing(const HTTPFetchRequest &request_,
 229                 CurlHandlePool *pool_):
 230         pool(pool_),
 231         curl(NULL),
 232         multi(NULL),
 233         request(request_),
 234         result(request_),
 235         oss(std::ios::binary),
 236         http_header(NULL),
 237         post(NULL)
 238 {
 239         curl = pool->alloc();
 240         if (curl == NULL) {
 241                 return;
 242         }
 243
 244         // Set static cURL options
 245         curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);
 246         curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1);
 247         curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1);
 248         curl_easy_setopt(curl, CURLOPT_MAXREDIRS, 3);
 249         curl_easy_setopt(curl, CURLOPT_ENCODING, "gzip");
 250
 251         std::string bind_address = g_settings->get("bind_address");
 252         if (!bind_address.empty()) {
 253                 curl_easy_setopt(curl, CURLOPT_INTERFACE, bind_address.c_str());
 254         }
 255
 256         if (!g_settings->getBool("enable_ipv6")) {
 257                 curl_easy_setopt(curl, CURLOPT_IPRESOLVE, CURL_IPRESOLVE_V4);
 258         }
 259
 260 #if LIBCURL_VERSION_NUM >= 0x071304
 261         // Restrict protocols so that curl vulnerabilities in
 262         // other protocols don't affect us.
 263         // These settings were introduced in curl 7.19.4.
 264         long protocols =
 265                 CURLPROTO_HTTP |
 266                 CURLPROTO_HTTPS |
 267                 CURLPROTO_FTP |
 268                 CURLPROTO_FTPS;
 269         curl_easy_setopt(curl, CURLOPT_PROTOCOLS, protocols);
 270         curl_easy_setopt(curl, CURLOPT_REDIR_PROTOCOLS, protocols);
 271 #endif
 272
 273         // Set cURL options based on HTTPFetchRequest
 274         curl_easy_setopt(curl, CURLOPT_URL,
 275                         request.url.c_str());
 276         curl_easy_setopt(curl, CURLOPT_TIMEOUT_MS,
 277                         request.timeout);
 278         curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT_MS,
 279                         request.connect_timeout);
 280
 281         if (!request.useragent.empty())
 282                 curl_easy_setopt(curl, CURLOPT_USERAGENT, request.useragent.c_str());
 283
 284         // Set up a write callback that writes to the
 285         // ostringstream ongoing->oss, unless the data
 286         // is to be discarded
 287         if (request.caller == HTTPFETCH_DISCARD) {
 288                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 289                                 httpfetch_discardfunction);
 290                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
 291         } else {
 292                 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 293                                 httpfetch_writefunction);
 294                 curl_easy_setopt(curl, CURLOPT_WRITEDATA, &oss);
 295         }
 296
 297         // Set data from fields or raw_data
 298         if (request.multipart) {
 299                 curl_httppost *last = NULL;
 300                 for (StringMap::iterator it = request.fields.begin();
 301                                 it != request.fields.end(); ++it) {
 302                         curl_formadd(&post, &last,
 303                                         CURLFORM_NAMELENGTH, it->first.size(),
 304                                         CURLFORM_PTRNAME, it->first.c_str(),
 305                                         CURLFORM_CONTENTSLENGTH, it->second.size(),
 306                                         CURLFORM_PTRCONTENTS, it->second.c_str(),
 307                                         CURLFORM_END);
 308                 }
 309                 curl_easy_setopt(curl, CURLOPT_HTTPPOST, post);
 310                 // request.post_fields must now *never* be
 311                 // modified until CURLOPT_HTTPPOST is cleared
 312         } else {
 313                 switch (request.method) {
 314                 case HTTP_GET:
 315                         curl_easy_setopt(curl, CURLOPT_HTTPGET, 1);
 316                         break;
 317                 case HTTP_POST:
 318                         curl_easy_setopt(curl, CURLOPT_POST, 1);
 319                         break;
 320                 case HTTP_PUT:
 321                         curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "PUT");
 322                         break;
 323                 case HTTP_DELETE:
 324                         curl_easy_setopt(curl, CURLOPT_CUSTOMREQUEST, "DELETE");
 325                         break;
 326                 }
 327                 if (request.method != HTTP_GET) {
 328                         if (!request.raw_data.empty()) {
 329                                 curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
 330                                                 request.raw_data.size());
 331                                 curl_easy_setopt(curl, CURLOPT_POSTFIELDS,
 332                                                 request.raw_data.c_str());
 333                         } else if (!request.fields.empty()) {
 334                                 std::string str;
 335                                 for (auto &field : request.fields) {
 336                                         if (!str.empty())
 337                                                 str += "&";
 338                                         str += urlencode(field.first);
 339                                         str += "=";
 340                                         str += urlencode(field.second);
 341                                 }
 342                                 curl_easy_setopt(curl, CURLOPT_POSTFIELDSIZE,
 343                                                 str.size());
 344                                 curl_easy_setopt(curl, CURLOPT_COPYPOSTFIELDS,
 345                                                 str.c_str());
 346                         }
 347                 }
 348         }
 349         // Set additional HTTP headers
 350         for (const std::string &extra_header : request.extra_headers) {
 351                 http_header = curl_slist_append(http_header, extra_header.c_str());
 352         }
 353         curl_easy_setopt(curl, CURLOPT_HTTPHEADER, http_header);
 354
 355         if (!g_settings->getBool("curl_verify_cert")) {
 356                 curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, false);
 357         }
 358 }
 359
 360 CURLcode HTTPFetchOngoing::start(CURLM *multi_)
 361 {
 362         if (!curl)
 363                 return CURLE_FAILED_INIT;
 364
 365         if (!multi_) {
 366                 // Easy interface (sync)
 367                 return curl_easy_perform(curl);
 368         }
 369
 370         // Multi interface (async)
 371         CURLMcode mres = curl_multi_add_handle(multi_, curl);
 372         if (mres != CURLM_OK) {
 373                 errorstream << "curl_multi_add_handle"
 374                         << " returned error code " << mres
 375                         << std::endl;
 376                 return CURLE_FAILED_INIT;
 377         }
 378         multi = multi_; // store for curl_multi_remove_handle
 379         return CURLE_OK;
 380 }
 381
 382 const HTTPFetchResult * HTTPFetchOngoing::complete(CURLcode res)
 383 {
 384         result.succeeded = (res == CURLE_OK);
 385         result.timeout = (res == CURLE_OPERATION_TIMEDOUT);
 386         result.data = oss.str();
 387
 388         // Get HTTP/FTP response code
 389         result.response_code = 0;
 390         if (curl && (curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE,
 391                                 &result.response_code) != CURLE_OK)) {
 392                 // We failed to get a return code, make sure it is still 0
 393                 result.response_code = 0;
 394         }
 395
 396         if (res != CURLE_OK) {
 397                 errorstream << request.url << " not found ("
 398                         << curl_easy_strerror(res) << ")"
 399                         << " (response code " << result.response_code << ")"
 400                         << std::endl;
 401         }
 402
 403         return &result;
 404 }
 405
 406 HTTPFetchOngoing::~HTTPFetchOngoing()
 407 {
 408         if (multi) {
 409                 CURLMcode mres = curl_multi_remove_handle(multi, curl);
 410                 if (mres != CURLM_OK) {
 411                         errorstream << "curl_multi_remove_handle"
 412                                 << " returned error code " << mres
 413                                 << std::endl;
 414                 }
 415         }
 416
 417         // Set safe options for the reusable cURL handle
 418         curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION,
 419                         httpfetch_discardfunction);
 420         curl_easy_setopt(curl, CURLOPT_WRITEDATA, NULL);
 421         curl_easy_setopt(curl, CURLOPT_POSTFIELDS, NULL);
 422         if (http_header) {
 423                 curl_easy_setopt(curl, CURLOPT_HTTPHEADER, NULL);
 424                 curl_slist_free_all(http_header);
 425         }
 426         if (post) {
 427                 curl_easy_setopt(curl, CURLOPT_HTTPPOST, NULL);
 428                 curl_formfree(post);
 429         }
 430
 431         // Store the cURL handle for reuse
 432         pool->free(curl);
 433 }
 434
 435
 436 class CurlFetchThread : public Thread
 437 {
 438 protected:
 439         enum RequestType {
 440                 RT_FETCH,
 441                 RT_CLEAR,
 442                 RT_WAKEUP,
 443         };
 444
 445         struct Request {
 446                 RequestType type;
 447                 HTTPFetchRequest fetch_request;
 448                 Event *event;
 449         };
 450
 451         CURLM *m_multi;
 452         MutexedQueue<Request> m_requests;
 453         size_t m_parallel_limit;
 454
 455         // Variables exclusively used within thread
 456         std::vector<HTTPFetchOngoing*> m_all_ongoing;
 457         std::list<HTTPFetchRequest> m_queued_fetches;
 458
 459 public:
 460         CurlFetchThread(int parallel_limit) :
 461                 Thread("CurlFetch")
 462         {
 463                 if (parallel_limit >= 1)
 464                         m_parallel_limit = parallel_limit;
 465                 else
 466                         m_parallel_limit = 1;
 467         }
 468
 469         void requestFetch(const HTTPFetchRequest &fetch_request)
 470         {
 471                 Request req;
 472                 req.type = RT_FETCH;
 473                 req.fetch_request = fetch_request;
 474                 req.event = NULL;
 475                 m_requests.push_back(req);
 476         }
 477
 478         void requestClear(unsigned long caller, Event *event)
 479         {
 480                 Request req;
 481                 req.type = RT_CLEAR;
 482                 req.fetch_request.caller = caller;
 483                 req.event = event;
 484                 m_requests.push_back(req);
 485         }
 486
 487         void requestWakeUp()
 488         {
 489                 Request req;
 490                 req.type = RT_WAKEUP;
 491                 req.event = NULL;
 492                 m_requests.push_back(req);
 493         }
 494
 495 protected:
 496         // Handle a request from some other thread
 497         // E.g. new fetch; clear fetches for one caller; wake up
 498         void processRequest(const Request &req)
 499         {
 500                 if (req.type == RT_FETCH) {
 501                         // New fetch, queue until there are less
 502                         // than m_parallel_limit ongoing fetches
 503                         m_queued_fetches.push_back(req.fetch_request);
 504
 505                         // see processQueued() for what happens next
 506
 507                 }
 508                 else if (req.type == RT_CLEAR) {
 509                         unsigned long caller = req.fetch_request.caller;
 510
 511                         // Abort all ongoing fetches for the caller
 512                         for (std::vector<HTTPFetchOngoing*>::iterator
 513                                         it = m_all_ongoing.begin();
 514                                         it != m_all_ongoing.end();) {
 515                                 if ((*it)->getRequest().caller == caller) {
 516                                         delete (*it);
 517                                         it = m_all_ongoing.erase(it);
 518                                 } else {
 519                                         ++it;
 520                                 }
 521                         }
 522
 523                         // Also abort all queued fetches for the caller
 524                         for (std::list<HTTPFetchRequest>::iterator
 525                                         it = m_queued_fetches.begin();
 526                                         it != m_queued_fetches.end();) {
 527                                 if ((*it).caller == caller)
 528                                         it = m_queued_fetches.erase(it);
 529                                 else
 530                                         ++it;
 531                         }
 532                 }
 533                 else if (req.type == RT_WAKEUP) {
 534                         // Wakeup: Nothing to do, thread is awake at this point
 535                 }
 536
 537                 if (req.event != NULL)
 538                         req.event->signal();
 539         }
 540
 541         // Start new ongoing fetches if m_parallel_limit allows
 542         void processQueued(CurlHandlePool *pool)
 543         {
 544                 while (m_all_ongoing.size() < m_parallel_limit &&
 545                                 !m_queued_fetches.empty()) {
 546                         HTTPFetchRequest request = m_queued_fetches.front();
 547                         m_queued_fetches.pop_front();
 548
 549                         // Create ongoing fetch data and make a cURL handle
 550                         // Set cURL options based on HTTPFetchRequest
 551                         HTTPFetchOngoing *ongoing =
 552                                 new HTTPFetchOngoing(request, pool);
 553
 554                         // Initiate the connection (curl_multi_add_handle)
 555                         CURLcode res = ongoing->start(m_multi);
 556                         if (res == CURLE_OK) {
 557                                 m_all_ongoing.push_back(ongoing);
 558                         }
 559                         else {
 560                                 httpfetch_deliver_result(*ongoing->complete(res));
 561                                 delete ongoing;
 562                         }
 563                 }
 564         }
 565
 566         // Process CURLMsg (indicates completion of a fetch)
 567         void processCurlMessage(CURLMsg *msg)
 568         {
 569                 // Determine which ongoing fetch the message pertains to
 570                 size_t i = 0;
 571                 bool found = false;
 572                 for (i = 0; i < m_all_ongoing.size(); ++i) {
 573                         if (m_all_ongoing[i]->getEasyHandle() == msg->easy_handle) {
 574                                 found = true;
 575                                 break;
 576                         }
 577                 }
 578                 if (msg->msg == CURLMSG_DONE && found) {
 579                         // m_all_ongoing[i] succeeded or failed.
 580                         HTTPFetchOngoing *ongoing = m_all_ongoing[i];
 581                         httpfetch_deliver_result(*ongoing->complete(msg->data.result));
 582                         delete ongoing;
 583                         m_all_ongoing.erase(m_all_ongoing.begin() + i);
 584                 }
 585         }
 586
 587         // Wait for a request from another thread, or timeout elapses
 588         void waitForRequest(long timeout)
 589         {
 590                 if (m_queued_fetches.empty()) {
 591                         try {
 592                                 Request req = m_requests.pop_front(timeout);
 593                                 processRequest(req);
 594                         }
 595                         catch (ItemNotFoundException &e) {}
 596                 }
 597         }
 598
 599         // Wait until some IO happens, or timeout elapses
 600         void waitForIO(long timeout)
 601         {
 602                 fd_set read_fd_set;
 603                 fd_set write_fd_set;
 604                 fd_set exc_fd_set;
 605                 int max_fd;
 606                 long select_timeout = -1;
 607                 struct timeval select_tv;
 608                 CURLMcode mres;
 609
 610                 FD_ZERO(&read_fd_set);
 611                 FD_ZERO(&write_fd_set);
 612                 FD_ZERO(&exc_fd_set);
 613
 614                 mres = curl_multi_fdset(m_multi, &read_fd_set,
 615                                 &write_fd_set, &exc_fd_set, &max_fd);
 616                 if (mres != CURLM_OK) {
 617                         errorstream<<"curl_multi_fdset"
 618                                 <<" returned error code "<<mres
 619                                 <<std::endl;
 620                         select_timeout = 0;
 621                 }
 622
 623                 mres = curl_multi_timeout(m_multi, &select_timeout);
 624                 if (mres != CURLM_OK) {
 625                         errorstream<<"curl_multi_timeout"
 626                                 <<" returned error code "<<mres
 627                                 <<std::endl;
 628                         select_timeout = 0;
 629                 }
 630
 631                 // Limit timeout so new requests get through
 632                 if (select_timeout < 0 || select_timeout > timeout)
 633                         select_timeout = timeout;
 634
 635                 if (select_timeout > 0) {
 636                         // in Winsock it is forbidden to pass three empty
 637                         // fd_sets to select(), so in that case use sleep_ms
 638                         if (max_fd != -1) {
 639                                 select_tv.tv_sec = select_timeout / 1000;
 640                                 select_tv.tv_usec = (select_timeout % 1000) * 1000;
 641                                 int retval = select(max_fd + 1, &read_fd_set,
 642                                                 &write_fd_set, &exc_fd_set,
 643                                                 &select_tv);
 644                                 if (retval == -1) {
 645                                         #ifdef _WIN32
 646                                         errorstream<<"select returned error code "
 647                                                 <<WSAGetLastError()<<std::endl;
 648                                         #else
 649                                         errorstream<<"select returned error code "
 650                                                 <<errno<<std::endl;
 651                                         #endif
 652                                 }
 653                         }
 654                         else {
 655                                 sleep_ms(select_timeout);
 656                         }
 657                 }
 658         }
 659
 660         void *run()
 661         {
 662                 CurlHandlePool pool;
 663
 664                 m_multi = curl_multi_init();
 665                 if (m_multi == NULL) {
 666                         errorstream<<"curl_multi_init returned NULL\n";
 667                         return NULL;
 668                 }
 669
 670                 FATAL_ERROR_IF(!m_all_ongoing.empty(), "Expected empty");
 671
 672                 while (!stopRequested()) {
 673                         BEGIN_DEBUG_EXCEPTION_HANDLER
 674
 675                         /*
 676                                 Handle new async requests
 677                         */
 678
 679                         while (!m_requests.empty()) {
 680                                 Request req = m_requests.pop_frontNoEx();
 681                                 processRequest(req);
 682                         }
 683                         processQueued(&pool);
 684
 685                         /*
 686                                 Handle ongoing async requests
 687                         */
 688
 689                         int still_ongoing = 0;
 690                         while (curl_multi_perform(m_multi, &still_ongoing) ==
 691                                         CURLM_CALL_MULTI_PERFORM)
 692                                 /* noop */;
 693
 694                         /*
 695                                 Handle completed async requests
 696                         */
 697                         if (still_ongoing < (int) m_all_ongoing.size()) {
 698                                 CURLMsg *msg;
 699                                 int msgs_in_queue;
 700                                 msg = curl_multi_info_read(m_multi, &msgs_in_queue);
 701                                 while (msg != NULL) {
 702                                         processCurlMessage(msg);
 703                                         msg = curl_multi_info_read(m_multi, &msgs_in_queue);
 704                                 }
 705                         }
 706
 707                         /*
 708                                 If there are ongoing requests, wait for data
 709                                 (with a timeout of 100ms so that new requests
 710                                 can be processed).
 711
 712                                 If no ongoing requests, wait for a new request.
 713                                 (Possibly an empty request that signals
 714                                 that the thread should be stopped.)
 715                         */
 716                         if (m_all_ongoing.empty())
 717                                 waitForRequest(100000000);
 718                         else
 719                                 waitForIO(100);
 720
 721                         END_DEBUG_EXCEPTION_HANDLER
 722                 }
 723
 724                 // Call curl_multi_remove_handle and cleanup easy handles
 725                 for (HTTPFetchOngoing *i : m_all_ongoing) {
 726                         delete i;
 727                 }
 728                 m_all_ongoing.clear();
 729
 730                 m_queued_fetches.clear();
 731
 732                 CURLMcode mres = curl_multi_cleanup(m_multi);
 733                 if (mres != CURLM_OK) {
 734                         errorstream<<"curl_multi_cleanup"
 735                                 <<" returned error code "<<mres
 736                                 <<std::endl;
 737                 }
 738
 739                 return NULL;
 740         }
 741 };
 742
 743 CurlFetchThread *g_httpfetch_thread = NULL;
 744
 745 void httpfetch_init(int parallel_limit)
 746 {
 747         verbosestream<<"httpfetch_init: parallel_limit="<<parallel_limit
 748                         <<std::endl;
 749
 750         CURLcode res = curl_global_init(CURL_GLOBAL_DEFAULT);
 751         FATAL_ERROR_IF(res != CURLE_OK, "CURL init failed");
 752
 753         g_httpfetch_thread = new CurlFetchThread(parallel_limit);
 754
 755         // Initialize g_callerid_randomness for httpfetch_caller_alloc_secure
 756         u64 randbuf[2];
 757         porting::secure_rand_fill_buf(randbuf, sizeof(u64) * 2);
 758         g_callerid_randomness = PcgRandom(randbuf[0], randbuf[1]);
 759 }
 760
 761 void httpfetch_cleanup()
 762 {
 763         verbosestream<<"httpfetch_cleanup: cleaning up"<<std::endl;
 764
 765         g_httpfetch_thread->stop();
 766         g_httpfetch_thread->requestWakeUp();
 767         g_httpfetch_thread->wait();
 768         delete g_httpfetch_thread;
 769
 770         curl_global_cleanup();
 771 }
 772
 773 void httpfetch_async(const HTTPFetchRequest &fetch_request)
 774 {
 775         g_httpfetch_thread->requestFetch(fetch_request);
 776         if (!g_httpfetch_thread->isRunning())
 777                 g_httpfetch_thread->start();
 778 }
 779
 780 static void httpfetch_request_clear(unsigned long caller)
 781 {
 782         if (g_httpfetch_thread->isRunning()) {
 783                 Event event;
 784                 g_httpfetch_thread->requestClear(caller, &event);
 785                 event.wait();
 786         } else {
 787                 g_httpfetch_thread->requestClear(caller, NULL);
 788         }
 789 }
 790
 791 void httpfetch_sync(const HTTPFetchRequest &fetch_request,
 792                 HTTPFetchResult &fetch_result)
 793 {
 794         // Create ongoing fetch data and make a cURL handle
 795         // Set cURL options based on HTTPFetchRequest
 796         CurlHandlePool pool;
 797         HTTPFetchOngoing ongoing(fetch_request, &pool);
 798         // Do the fetch (curl_easy_perform)
 799         CURLcode res = ongoing.start(NULL);
 800         // Update fetch result
 801         fetch_result = *ongoing.complete(res);
 802 }
 803
 804 #else  // USE_CURL
 805
 806 /*
 807         USE_CURL is off:
 808
 809         Dummy httpfetch implementation that always returns an error.
 810 */
 811
 812 void httpfetch_init(int parallel_limit)
 813 {
 814 }
 815
 816 void httpfetch_cleanup()
 817 {
 818 }
 819
 820 void httpfetch_async(const HTTPFetchRequest &fetch_request)
 821 {
 822         errorstream << "httpfetch_async: unable to fetch " << fetch_request.url
 823                         << " because USE_CURL=0" << std::endl;
 824
 825         HTTPFetchResult fetch_result(fetch_request); // sets succeeded = false etc.
 826         httpfetch_deliver_result(fetch_result);
 827 }
 828
 829 static void httpfetch_request_clear(unsigned long caller)
 830 {
 831 }
 832
 833 void httpfetch_sync(const HTTPFetchRequest &fetch_request,
 834                 HTTPFetchResult &fetch_result)
 835 {
 836         errorstream << "httpfetch_sync: unable to fetch " << fetch_request.url
 837                         << " because USE_CURL=0" << std::endl;
 838
 839         fetch_result = HTTPFetchResult(fetch_request); // sets succeeded = false etc.
 840 }
 841
 842 #endif  // USE_CURL