src/transport/plugin_transport_http_client.c

   1 /*
   2      This file is part of GNUnet
   3      Copyright (C) 2002-2014 Christian Grothoff (and other contributing authors)
   4
   5      GNUnet is free software; you can redistribute it and/or modify
   6      it under the terms of the GNU General Public License as published
   7      by the Free Software Foundation; either version 3, or (at your
   8      option) any later version.
   9
  10      GNUnet is distributed in the hope that it will be useful, but
  11      WITHOUT ANY WARRANTY; without even the implied warranty of
  12      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13      General Public License for more details.
  14
  15      You should have received a copy of the GNU General Public License
  16      along with GNUnet; see the file COPYING.  If not, write to the
  17      Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  18      Boston, MA 02110-1301, USA.
  19 */
  20
  21 /**
  22  * @file transport/plugin_transport_http_client.c
  23  * @brief HTTP/S client transport plugin
  24  * @author Matthias Wachs
  25  * @author Christian Grothoff
  26  */
  27
  28 #if BUILD_HTTPS
  29 #define PLUGIN_NAME "https_client"
  30 #define HTTP_STAT_STR_CONNECTIONS "# HTTPS client connections"
  31 #define LIBGNUNET_PLUGIN_TRANSPORT_INIT libgnunet_plugin_transport_https_client_init
  32 #define LIBGNUNET_PLUGIN_TRANSPORT_DONE libgnunet_plugin_transport_https_client_done
  33 #else
  34 #define PLUGIN_NAME "http_client"
  35 #define HTTP_STAT_STR_CONNECTIONS "# HTTP client connections"
  36 #define LIBGNUNET_PLUGIN_TRANSPORT_INIT libgnunet_plugin_transport_http_client_init
  37 #define LIBGNUNET_PLUGIN_TRANSPORT_DONE libgnunet_plugin_transport_http_client_done
  38 #endif
  39
  40 #define VERBOSE_CURL GNUNET_NO
  41
  42 #define PUT_DISCONNECT_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1)
  43
  44 #define ENABLE_PUT GNUNET_YES
  45 #define ENABLE_GET GNUNET_YES
  46
  47 #include "platform.h"
  48 #include "gnunet_util_lib.h"
  49 #include "gnunet_protocols.h"
  50 #include "gnunet_transport_plugin.h"
  51 #include "plugin_transport_http_common.h"
  52 #if HAVE_CURL_CURL_H
  53 #include <curl/curl.h>
  54 #elif HAVE_GNURL_CURL_H
  55 #include <gnurl/curl.h>
  56 #endif
  57
  58
  59 #define LOG(kind,...) GNUNET_log_from(kind, PLUGIN_NAME, __VA_ARGS__)
  60
  61 /**
  62  * Encapsulation of all of the state of the plugin.
  63  */
  64 struct HTTP_Client_Plugin;
  65
  66 /**
  67  * State of a HTTP PUT request
  68  */
  69 enum HTTP_PUT_REQUEST_STATE
  70 {
  71   /**
  72    *  Just created, not yet connected
  73    */
  74   H_NOT_CONNECTED,
  75
  76   /**
  77    *  Connected
  78    */
  79   H_CONNECTED,
  80
  81   /**
  82    *  Paused, nothing to send
  83    */
  84   H_PAUSED,
  85
  86   /**
  87    * Temporary disconnect in progress due to inactivity
  88    */
  89   H_TMP_DISCONNECTING,
  90
  91   /**
  92    * Send request while temporary disconnect, reconnect
  93    */
  94   H_TMP_RECONNECT_REQUIRED,
  95
  96   /**
  97    * Temporarily disconnected
  98    */
  99   H_TMP_DISCONNECTED,
 100
 101   /**
 102    * Disconnected
 103    */
 104   H_DISCONNECTED
 105 };
 106
 107 /**
 108  *  Message to send using http
 109  */
 110 struct HTTP_Message
 111 {
 112   /**
 113    * next pointer for double linked list
 114    */
 115   struct HTTP_Message *next;
 116
 117   /**
 118    * previous pointer for double linked list
 119    */
 120   struct HTTP_Message *prev;
 121
 122   /**
 123    * buffer containing data to send
 124    */
 125   char *buf;
 126
 127   /**
 128    * Continuation function to call once the transmission buffer
 129    * has again space available.  NULL if there is no
 130    * continuation to call.
 131    */
 132   GNUNET_TRANSPORT_TransmitContinuation transmit_cont;
 133
 134   /**
 135    * Closure for @e transmit_cont.
 136    */
 137   void *transmit_cont_cls;
 138
 139   /**
 140    * amount of data already sent
 141    */
 142   size_t pos;
 143
 144   /**
 145    * buffer length
 146    */
 147   size_t size;
 148
 149 };
 150
 151
 152 /**
 153  * Session handle for HTTP(S) connections.
 154  */
 155 struct Session;
 156
 157
 158 /**
 159  * A request handle
 160  *
 161  */
 162 struct RequestHandle
 163 {
 164   /**
 165    * Current state of this request
 166    */
 167   enum HTTP_PUT_REQUEST_STATE state;
 168
 169   /**
 170    * The curl easy handle
 171    */
 172   CURL *easyhandle;
 173
 174   /**
 175    * The related session
 176    */
 177   struct Session *s;
 178 };
 179
 180
 181 /**
 182  * Session handle for connections.
 183  */
 184 struct Session
 185 {
 186   /**
 187    * The URL to connect to
 188    */
 189   char *url;
 190
 191   /**
 192    * Address
 193    */
 194   struct GNUNET_HELLO_Address *address;
 195
 196   /**
 197    * Pointer to the global plugin struct.
 198    */
 199   struct HTTP_Client_Plugin *plugin;
 200
 201   /**
 202    * Handle for the HTTP PUT request.
 203    */
 204   struct RequestHandle put;
 205
 206   /**
 207    * Handle for the HTTP GET request.
 208    */
 209   struct RequestHandle get;
 210
 211   /**
 212    * next pointer for double linked list
 213    */
 214   struct HTTP_Message *msg_head;
 215
 216   /**
 217    * previous pointer for double linked list
 218    */
 219   struct HTTP_Message *msg_tail;
 220
 221   /**
 222    * Message stream tokenizer for incoming data
 223    */
 224   struct GNUNET_SERVER_MessageStreamTokenizer *msg_tk;
 225
 226   /**
 227    * Session timeout task
 228    */
 229   struct GNUNET_SCHEDULER_Task * put_disconnect_task;
 230
 231   /**
 232    * Session timeout task
 233    */
 234   struct GNUNET_SCHEDULER_Task * timeout_task;
 235
 236   /**
 237    * Task to wake up client receive handle when receiving is allowed again
 238    */
 239   struct GNUNET_SCHEDULER_Task * recv_wakeup_task;
 240
 241   /**
 242    * Absolute time when to receive data again.
 243    * Used for receive throttling.
 244    */
 245   struct GNUNET_TIME_Absolute next_receive;
 246
 247   /**
 248    * When does this session time out.
 249    */
 250   struct GNUNET_TIME_Absolute timeout;
 251
 252   /**
 253    * Number of bytes waiting for transmission to this peer.
 254    */
 255   unsigned long long bytes_in_queue;
 256
 257   /**
 258    * Outbound overhead due to HTTP connection
 259    * Add to next message of this session when calling callback
 260    */
 261   size_t overhead;
 262
 263   /**
 264    * Number of messages waiting for transmission to this peer.
 265    */
 266   unsigned int msgs_in_queue;
 267
 268   /**
 269    * ATS network type.
 270    */
 271   enum GNUNET_ATS_Network_Type scope;
 272 };
 273
 274
 275 /**
 276  * Encapsulation of all of the state of the plugin.
 277  */
 278 struct HTTP_Client_Plugin
 279 {
 280   /**
 281    * Our environment.
 282    */
 283   struct GNUNET_TRANSPORT_PluginEnvironment *env;
 284
 285   /**
 286    * Open sessions.
 287    */
 288   struct GNUNET_CONTAINER_MultiPeerMap *sessions;
 289
 290   /**
 291    * Function to call about session status changes.
 292    */
 293   GNUNET_TRANSPORT_SessionInfoCallback sic;
 294
 295   /**
 296    * Closure for @e sic.
 297    */
 298   void *sic_cls;
 299
 300   /**
 301    * Plugin name
 302    */
 303   char *name;
 304
 305   /**
 306    * Protocol
 307    */
 308   char *protocol;
 309
 310   /**
 311    * Proxy configuration: hostname or ip of the proxy server
 312    */
 313   char *proxy_hostname;
 314
 315   /**
 316    * Username for the proxy server
 317    */
 318   char *proxy_username;
 319
 320   /**
 321    * Password for the proxy server
 322    */
 323   char *proxy_password;
 324
 325   /**
 326    * cURL Multihandle
 327    */
 328   CURLM *curl_multi_handle;
 329
 330   /**
 331    * curl perform task
 332    */
 333   struct GNUNET_SCHEDULER_Task * client_perform_task;
 334
 335   /**
 336    * Type of proxy server:
 337    *
 338    * Valid values as supported by curl:
 339    * CURLPROXY_HTTP, CURLPROXY_HTTP_1_0 CURLPROXY_SOCKS4, CURLPROXY_SOCKS5,
 340    * CURLPROXY_SOCKS4A, CURLPROXY_SOCKS5_HOSTNAME
 341    */
 342   curl_proxytype proxytype;
 343
 344   /**
 345    * Use proxy tunneling:
 346    * Tunnel all operations through a given HTTP instead of have the proxy
 347    * evaluate the HTTP request
 348    *
 349    * Default: #GNUNET_NO, #GNUNET_YES experimental
 350    */
 351   int proxy_use_httpproxytunnel;
 352
 353   /**
 354    * My options to be included in the address
 355    */
 356   uint32_t options;
 357
 358   /**
 359    * Maximum number of sockets the plugin can use
 360    * Each http connections are two requests
 361    */
 362   unsigned int max_requests;
 363
 364   /**
 365    * Current number of sockets the plugin can use
 366    * Each http connections are two requests
 367    */
 368   unsigned int cur_requests;
 369
 370   /**
 371    * Last used unique HTTP connection tag
 372    */
 373   uint32_t last_tag;
 374
 375   /**
 376    * use IPv6
 377    */
 378   uint16_t use_ipv6;
 379
 380   /**
 381    * use IPv4
 382    */
 383   uint16_t use_ipv4;
 384
 385   /**
 386    * Should we emulate an XHR client for testing?
 387    */
 388   int emulate_xhr;
 389 };
 390
 391
 392 /**
 393  * Disconnect a session
 394  *
 395  * @param cls the `struct HTTP_Client_Plugin *`
 396  * @param s session
 397  * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
 398  */
 399 static int
 400 http_client_plugin_session_disconnect (void *cls, struct Session *s);
 401
 402
 403 /**
 404  * If a session monitor is attached, notify it about the new
 405  * session state.
 406  *
 407  * @param plugin our plugin
 408  * @param session session that changed state
 409  * @param state new state of the session
 410  */
 411 static void
 412 notify_session_monitor (struct HTTP_Client_Plugin *plugin,
 413                         struct Session *session,
 414                         enum GNUNET_TRANSPORT_SessionState state)
 415 {
 416   struct GNUNET_TRANSPORT_SessionInfo info;
 417
 418   if (NULL == plugin->sic)
 419     return;
 420   memset (&info, 0, sizeof (info));
 421   info.state = state;
 422   info.is_inbound = GNUNET_NO;
 423   info.num_msg_pending = session->msgs_in_queue;
 424   info.num_bytes_pending = session->bytes_in_queue;
 425   info.receive_delay = session->next_receive;
 426   info.session_timeout = session->timeout;
 427   info.address = session->address;
 428   plugin->sic (plugin->sic_cls,
 429                session,
 430                &info);
 431 }
 432
 433
 434 /**
 435  * Delete session @a s.
 436  *
 437  * @param s the session to delete
 438  */
 439 static void
 440 client_delete_session (struct Session *s)
 441 {
 442   struct HTTP_Client_Plugin *plugin = s->plugin;
 443   struct HTTP_Message *pos;
 444   struct HTTP_Message *next;
 445   CURLMcode mret;
 446
 447   if (NULL != s->timeout_task)
 448   {
 449     GNUNET_SCHEDULER_cancel (s->timeout_task);
 450     s->timeout_task = NULL;
 451     s->timeout = GNUNET_TIME_UNIT_ZERO_ABS;
 452   }
 453   if (NULL != s->put_disconnect_task)
 454   {
 455     GNUNET_SCHEDULER_cancel (s->put_disconnect_task);
 456     s->put_disconnect_task = NULL;
 457   }
 458   if (NULL != s->recv_wakeup_task)
 459   {
 460     GNUNET_SCHEDULER_cancel (s->recv_wakeup_task);
 461     s->recv_wakeup_task = NULL;
 462   }
 463   GNUNET_assert (GNUNET_OK ==
 464                  GNUNET_CONTAINER_multipeermap_remove (plugin->sessions,
 465                                                        &s->address->peer,
 466                                                        s));
 467   if (NULL != s->put.easyhandle)
 468   {
 469     LOG (GNUNET_ERROR_TYPE_DEBUG,
 470          "Session %p/request %p: disconnecting PUT request to peer `%s'\n",
 471          s,
 472          s->put.easyhandle,
 473          GNUNET_i2s (&s->address->peer));
 474
 475     /* remove curl handle from multi handle */
 476     mret = curl_multi_remove_handle (plugin->curl_multi_handle,
 477                                      s->put.easyhandle);
 478     GNUNET_break (CURLM_OK == mret);
 479     curl_easy_cleanup (s->put.easyhandle);
 480     GNUNET_assert (plugin->cur_requests > 0);
 481     plugin->cur_requests--;
 482     s->put.easyhandle = NULL;
 483   }
 484   if (NULL != s->get.easyhandle)
 485   {
 486     LOG (GNUNET_ERROR_TYPE_DEBUG,
 487          "Session %p/request %p: disconnecting GET request to peer `%s'\n",
 488          s, s->get.easyhandle,
 489          GNUNET_i2s (&s->address->peer));
 490     /* remove curl handle from multi handle */
 491     mret = curl_multi_remove_handle (plugin->curl_multi_handle,
 492                                      s->get.easyhandle);
 493     GNUNET_break (CURLM_OK == mret);
 494     curl_easy_cleanup (s->get.easyhandle);
 495     GNUNET_assert (plugin->cur_requests > 0);
 496     plugin->cur_requests--;
 497     s->get.easyhandle = NULL;
 498   }
 499
 500   GNUNET_STATISTICS_set (plugin->env->stats,
 501                          HTTP_STAT_STR_CONNECTIONS,
 502                          plugin->cur_requests,
 503                          GNUNET_NO);
 504   next = s->msg_head;
 505   while (NULL != (pos = next))
 506   {
 507     next = pos->next;
 508     GNUNET_CONTAINER_DLL_remove (s->msg_head,
 509                                  s->msg_tail,
 510                                  pos);
 511     GNUNET_assert (0 < s->msgs_in_queue);
 512     s->msgs_in_queue--;
 513     GNUNET_assert (pos->size <= s->bytes_in_queue);
 514     s->bytes_in_queue -= pos->size;
 515     if (NULL != pos->transmit_cont)
 516       pos->transmit_cont (pos->transmit_cont_cls,
 517                           &s->address->peer,
 518                           GNUNET_SYSERR,
 519                           pos->size,
 520                           pos->pos + s->overhead);
 521     s->overhead = 0;
 522     GNUNET_free (pos);
 523   }
 524   GNUNET_assert (0 == s->msgs_in_queue);
 525   GNUNET_assert (0 == s->bytes_in_queue);
 526   notify_session_monitor (plugin,
 527                           s,
 528                           GNUNET_TRANSPORT_SS_DONE);
 529   if (NULL != s->msg_tk)
 530   {
 531     GNUNET_SERVER_mst_destroy (s->msg_tk);
 532     s->msg_tk = NULL;
 533   }
 534   GNUNET_HELLO_address_free (s->address);
 535   GNUNET_free (s->url);
 536   GNUNET_free (s);
 537 }
 538
 539
 540 /**
 541  * Increment session timeout due to activity for session @a s.
 542  *
 543  * @param s the session
 544  */
 545 static void
 546 client_reschedule_session_timeout (struct Session *s)
 547 {
 548   GNUNET_assert (NULL != s->timeout_task);
 549   s->timeout = GNUNET_TIME_relative_to_absolute (GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT);
 550 }
 551
 552
 553 /**
 554  * Task performing curl operations
 555  *
 556  * @param cls plugin as closure
 557  * @param tc gnunet scheduler task context
 558  */
 559 static void
 560 client_run (void *cls,
 561             const struct GNUNET_SCHEDULER_TaskContext *tc);
 562
 563
 564 /**
 565  * Function setting up file descriptors and scheduling task to run
 566  *
 567  * @param plugin the plugin as closure
 568  * @param now schedule task in 1ms, regardless of what curl may say
 569  * @return #GNUNET_SYSERR for hard failure, #GNUNET_OK for ok
 570  */
 571 static int
 572 client_schedule (struct HTTP_Client_Plugin *plugin,
 573                  int now)
 574 {
 575   fd_set rs;
 576   fd_set ws;
 577   fd_set es;
 578   int max;
 579   struct GNUNET_NETWORK_FDSet *grs;
 580   struct GNUNET_NETWORK_FDSet *gws;
 581   long to;
 582   CURLMcode mret;
 583   struct GNUNET_TIME_Relative timeout;
 584
 585   /* Cancel previous scheduled task */
 586   if (plugin->client_perform_task != NULL)
 587   {
 588     GNUNET_SCHEDULER_cancel (plugin->client_perform_task);
 589     plugin->client_perform_task = NULL;
 590   }
 591   max = -1;
 592   FD_ZERO (&rs);
 593   FD_ZERO (&ws);
 594   FD_ZERO (&es);
 595   mret = curl_multi_fdset (plugin->curl_multi_handle, &rs, &ws, &es, &max);
 596   if (mret != CURLM_OK)
 597   {
 598     LOG (GNUNET_ERROR_TYPE_ERROR,
 599          _("%s failed at %s:%d: `%s'\n"),
 600          "curl_multi_fdset",
 601          __FILE__,
 602          __LINE__,
 603          curl_multi_strerror (mret));
 604     return GNUNET_SYSERR;
 605   }
 606   mret = curl_multi_timeout (plugin->curl_multi_handle, &to);
 607   if (-1 == to)
 608     timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 1);
 609   else
 610     timeout = GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_MILLISECONDS, to);
 611   if (now == GNUNET_YES)
 612     timeout = GNUNET_TIME_UNIT_MILLISECONDS;
 613
 614   if (CURLM_OK != mret)
 615   {
 616     LOG (GNUNET_ERROR_TYPE_ERROR,
 617                 _("%s failed at %s:%d: `%s'\n"),
 618                 "curl_multi_timeout", __FILE__, __LINE__,
 619                 curl_multi_strerror (mret));
 620     return GNUNET_SYSERR;
 621   }
 622
 623   grs = GNUNET_NETWORK_fdset_create ();
 624   gws = GNUNET_NETWORK_fdset_create ();
 625   GNUNET_NETWORK_fdset_copy_native (grs, &rs, max + 1);
 626   GNUNET_NETWORK_fdset_copy_native (gws, &ws, max + 1);
 627
 628   /* Schedule task to run when select is ready to read or write */
 629   plugin->client_perform_task =
 630       GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
 631                                    timeout, grs, gws,
 632                                    &client_run, plugin);
 633   GNUNET_NETWORK_fdset_destroy (gws);
 634   GNUNET_NETWORK_fdset_destroy (grs);
 635   return GNUNET_OK;
 636 }
 637
 638
 639 #if VERBOSE_CURL
 640 /**
 641  * Loggging function
 642  *
 643  * @param curl the curl easy handle
 644  * @param type message type
 645  * @param data data to log, NOT a 0-terminated string
 646  * @param size data length
 647  * @param cls the closure
 648  * @return always 0
 649  */
 650 static int
 651 client_log (CURL *curl,
 652             curl_infotype type,
 653             const char *data,
 654             size_t size,
 655             void *cls)
 656 {
 657   struct RequestHandle *ch = cls;
 658   const char *ttype = "UNSPECIFIED";
 659   char text[size + 2];
 660
 661   if (! ((CURLINFO_TEXT == type) ||
 662          (CURLINFO_HEADER_IN == type) ||
 663          (CURLINFO_HEADER_OUT == type)))
 664     return 0;
 665   switch (type)
 666   {
 667   case CURLINFO_TEXT:
 668     ttype = "TEXT";
 669     break;
 670   case CURLINFO_HEADER_IN:
 671     ttype = "HEADER_IN";
 672     break;
 673   case CURLINFO_HEADER_OUT:
 674     ttype = "HEADER_OUT";
 675     /* Overhead*/
 676     GNUNET_assert (NULL != ch);
 677     GNUNET_assert (NULL != ch->easyhandle);
 678     GNUNET_assert (NULL != ch->s);
 679     ch->s->overhead += size;
 680     break;
 681   default:
 682     ttype = "UNSPECIFIED";
 683     break;
 684   }
 685   memcpy (text, data, size);
 686   if (text[size - 1] == '\n')
 687   {
 688     text[size] = '\0';
 689   }
 690   else
 691   {
 692     text[size] = '\n';
 693     text[size + 1] = '\0';
 694   }
 695   LOG (GNUNET_ERROR_TYPE_DEBUG,
 696        "Request %p %s: %s",
 697        ch->easyhandle,
 698        ttype,
 699        text);
 700   return 0;
 701 }
 702 #endif
 703
 704 /**
 705  * Connect GET request
 706  *
 707  * @param s the session to connect
 708  * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
 709  */
 710 static int
 711 client_connect_get (struct Session *s);
 712
 713
 714 /**
 715  * Connect a HTTP put request
 716  *
 717  * @param s the session to connect
 718  * @return #GNUNET_SYSERR for hard failure, #GNUNET_OK for success
 719  */
 720 static int
 721 client_connect_put (struct Session *s);
 722
 723
 724 /**
 725  * Function that can be used by the transport service to transmit
 726  * a message using the plugin.   Note that in the case of a
 727  * peer disconnecting, the continuation MUST be called
 728  * prior to the disconnect notification itself.  This function
 729  * will be called with this peer's HELLO message to initiate
 730  * a fresh connection to another peer.
 731  *
 732  * @param cls closure
 733  * @param s which session must be used
 734  * @param msgbuf the message to transmit
 735  * @param msgbuf_size number of bytes in @a msgbuf
 736  * @param priority how important is the message (most plugins will
 737  *                 ignore message priority and just FIFO)
 738  * @param to how long to wait at most for the transmission (does not
 739  *                require plugins to discard the message after the timeout,
 740  *                just advisory for the desired delay; most plugins will ignore
 741  *                this as well)
 742  * @param cont continuation to call once the message has
 743  *        been transmitted (or if the transport is ready
 744  *        for the next transmission call; or if the
 745  *        peer disconnected...); can be NULL
 746  * @param cont_cls closure for @a cont
 747  * @return number of bytes used (on the physical network, with overheads);
 748  *         -1 on hard errors (i.e. address invalid); 0 is a legal value
 749  *         and does NOT mean that the message was not transmitted (DV)
 750  */
 751 static ssize_t
 752 http_client_plugin_send (void *cls,
 753                          struct Session *s,
 754                          const char *msgbuf,
 755                          size_t msgbuf_size,
 756                          unsigned int priority,
 757                          struct GNUNET_TIME_Relative to,
 758                          GNUNET_TRANSPORT_TransmitContinuation cont,
 759                          void *cont_cls)
 760 {
 761   struct HTTP_Client_Plugin *plugin = cls;
 762   struct HTTP_Message *msg;
 763   char *stat_txt;
 764
 765   LOG (GNUNET_ERROR_TYPE_DEBUG,
 766        "Session %p/request %p: Sending message with %u to peer `%s' \n",
 767        s,
 768        s->put.easyhandle,
 769        msgbuf_size,
 770        GNUNET_i2s (&s->address->peer));
 771
 772   /* create new message and schedule */
 773   msg = GNUNET_malloc (sizeof (struct HTTP_Message) + msgbuf_size);
 774   msg->size = msgbuf_size;
 775   msg->buf = (char *) &msg[1];
 776   msg->transmit_cont = cont;
 777   msg->transmit_cont_cls = cont_cls;
 778   memcpy (msg->buf,
 779           msgbuf,
 780           msgbuf_size);
 781   GNUNET_CONTAINER_DLL_insert_tail (s->msg_head,
 782                                     s->msg_tail,
 783                                     msg);
 784   s->msgs_in_queue++;
 785   s->bytes_in_queue += msg->size;
 786
 787   GNUNET_asprintf (&stat_txt,
 788                    "# bytes currently in %s_client buffers",
 789                    plugin->protocol);
 790   GNUNET_STATISTICS_update (plugin->env->stats,
 791                             stat_txt, msgbuf_size, GNUNET_NO);
 792   GNUNET_free (stat_txt);
 793   notify_session_monitor (plugin,
 794                           s,
 795                           GNUNET_TRANSPORT_SS_UPDATE);
 796   if (H_TMP_DISCONNECTING == s->put.state)
 797   {
 798     /* PUT request is currently getting disconnected */
 799     s->put.state = H_TMP_RECONNECT_REQUIRED;
 800     LOG (GNUNET_ERROR_TYPE_DEBUG,
 801          "Session %p/request %p: currently disconnecting, reconnecting immediately\n",
 802          s,
 803          s->put.easyhandle);
 804     return msgbuf_size;
 805   }
 806   if (H_PAUSED == s->put.state)
 807   {
 808     /* PUT request was paused, unpause */
 809     GNUNET_assert (s->put_disconnect_task != NULL);
 810     GNUNET_SCHEDULER_cancel (s->put_disconnect_task);
 811     s->put_disconnect_task = NULL;
 812     LOG (GNUNET_ERROR_TYPE_DEBUG,
 813          "Session %p/request %p: unpausing request\n",
 814          s, s->put.easyhandle);
 815     s->put.state = H_CONNECTED;
 816     if (NULL != s->put.easyhandle)
 817       curl_easy_pause (s->put.easyhandle, CURLPAUSE_CONT);
 818   }
 819   else if (H_TMP_DISCONNECTED == s->put.state)
 820   {
 821     /* PUT request was disconnected, reconnect */
 822     LOG (GNUNET_ERROR_TYPE_DEBUG, "Session %p: Reconnecting PUT request\n", s);
 823     GNUNET_break (NULL == s->put.easyhandle);
 824     if (GNUNET_SYSERR == client_connect_put (s))
 825     {
 826       /* Could not reconnect */
 827       http_client_plugin_session_disconnect (plugin, s);
 828       return GNUNET_SYSERR;
 829     }
 830   }
 831   client_schedule (s->plugin, GNUNET_YES);
 832   return msgbuf_size;
 833 }
 834
 835
 836 /**
 837  * Disconnect a session
 838  *
 839  * @param cls the `struct HTTP_Client_Plugin *`
 840  * @param s session
 841  * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
 842  */
 843 static int
 844 http_client_plugin_session_disconnect (void *cls,
 845                                        struct Session *s)
 846 {
 847   struct HTTP_Client_Plugin *plugin = cls;
 848
 849   LOG (GNUNET_ERROR_TYPE_DEBUG,
 850        "Session %p: notifying transport about ending session\n",
 851        s);
 852   plugin->env->session_end (plugin->env->cls,
 853                             s->address,
 854                             s);
 855   client_delete_session (s);
 856
 857   /* Re-schedule since handles have changed */
 858   if (NULL != plugin->client_perform_task)
 859   {
 860     GNUNET_SCHEDULER_cancel (plugin->client_perform_task);
 861     plugin->client_perform_task = NULL;
 862   }
 863   client_schedule (plugin, GNUNET_YES);
 864
 865   return GNUNET_OK;
 866 }
 867
 868
 869 /**
 870  * Function that is called to get the keepalive factor.
 871  * #GNUNET_CONSTANTS_IDLE_CONNECTION_TIMEOUT is divided by this number to
 872  * calculate the interval between keepalive packets.
 873  *
 874  * @param cls closure with the `struct Plugin`
 875  * @return keepalive factor
 876  */
 877 static unsigned int
 878 http_client_query_keepalive_factor (void *cls)
 879 {
 880   return 3;
 881 }
 882
 883
 884 /**
 885  * Callback to destroys all sessions on exit.
 886  *
 887  * @param cls the `struct HTTP_Client_Plugin *`
 888  * @param peer identity of the peer
 889  * @param value the `struct Session *`
 890  * @return #GNUNET_OK (continue iterating)
 891  */
 892 static int
 893 destroy_session_cb (void *cls,
 894                     const struct GNUNET_PeerIdentity *peer,
 895                     void *value)
 896 {
 897   struct HTTP_Client_Plugin *plugin = cls;
 898   struct Session *session = value;
 899
 900   http_client_plugin_session_disconnect (plugin, session);
 901   return GNUNET_OK;
 902 }
 903
 904
 905 /**
 906  * Function that can be used to force the plugin to disconnect
 907  * from the given peer and cancel all previous transmissions
 908  * (and their continuationc).
 909  *
 910  * @param cls closure
 911  * @param target peer from which to disconnect
 912  */
 913 static void
 914 http_client_plugin_peer_disconnect (void *cls,
 915                                     const struct GNUNET_PeerIdentity *target)
 916 {
 917   struct HTTP_Client_Plugin *plugin = cls;
 918
 919   LOG (GNUNET_ERROR_TYPE_DEBUG,
 920        "Transport tells me to disconnect `%s'\n",
 921        GNUNET_i2s (target));
 922   GNUNET_CONTAINER_multipeermap_get_multiple (plugin->sessions,
 923                                               target,
 924                                               &destroy_session_cb,
 925                                               plugin);
 926 }
 927
 928
 929 /**
 930  * Closure for #session_lookup_client_by_address().
 931  */
 932 struct SessionClientCtx
 933 {
 934   /**
 935    * Address we are looking for.
 936    */
 937   const struct GNUNET_HELLO_Address *address;
 938
 939   /**
 940    * Session that was found.
 941    */
 942   struct Session *ret;
 943 };
 944
 945
 946 /**
 947  * Locate the seession object for a given address.
 948  *
 949  * @param cls the `struct SessionClientCtx *`
 950  * @param key peer identity
 951  * @param value the `struct Session` to check
 952  * @return #GNUNET_NO if found, #GNUNET_OK if not
 953  */
 954 static int
 955 session_lookup_client_by_address (void *cls,
 956                                   const struct GNUNET_PeerIdentity *key,
 957                                   void *value)
 958 {
 959   struct SessionClientCtx *sc_ctx = cls;
 960   struct Session *s = value;
 961
 962   if (0 == GNUNET_HELLO_address_cmp (sc_ctx->address,
 963                                      s->address))
 964   {
 965     sc_ctx->ret = s;
 966     return GNUNET_NO;
 967   }
 968   return GNUNET_YES;
 969 }
 970
 971
 972 /**
 973  * Check if a sessions exists for an specific address
 974  *
 975  * @param plugin the plugin
 976  * @param address the address
 977  * @return the session or NULL
 978  */
 979 static struct Session *
 980 client_lookup_session (struct HTTP_Client_Plugin *plugin,
 981                        const struct GNUNET_HELLO_Address *address)
 982 {
 983   struct SessionClientCtx sc_ctx;
 984
 985   sc_ctx.address = address;
 986   sc_ctx.ret = NULL;
 987   GNUNET_CONTAINER_multipeermap_iterate (plugin->sessions,
 988                                          &session_lookup_client_by_address,
 989                                          &sc_ctx);
 990   return sc_ctx.ret;
 991 }
 992
 993
 994 /**
 995  * When we have nothing to transmit, we pause the HTTP PUT
 996  * after a while (so that gnurl stops asking).  This task
 997  * is the delayed task that actually disconnects the PUT.
 998  *
 999  * @param cls the `struct Session *` with the put
1000  * @param tc scheduler context
1001  */
1002 static void
1003 client_put_disconnect (void *cls,
1004                        const struct GNUNET_SCHEDULER_TaskContext *tc)
1005 {
1006   struct Session *s = cls;
1007
1008   s->put_disconnect_task = NULL;
1009   LOG (GNUNET_ERROR_TYPE_DEBUG,
1010        "Session %p/request %p: will be disconnected due to no activity\n",
1011        s, s->put.easyhandle);
1012   s->put.state = H_TMP_DISCONNECTING;
1013   if (NULL != s->put.easyhandle)
1014     curl_easy_pause (s->put.easyhandle,
1015                      CURLPAUSE_CONT);
1016   client_schedule (s->plugin, GNUNET_YES);
1017 }
1018
1019
1020 /**
1021  * Callback method used with libcurl
1022  * Method is called when libcurl needs to read data during sending
1023  *
1024  * @param stream pointer where to write data
1025  * @param size size of an individual element
1026  * @param nmemb count of elements that can be written to the buffer
1027  * @param cls our `struct Session`
1028  * @return bytes written to stream, returning 0 will terminate request!
1029  */
1030 static size_t
1031 client_send_cb (void *stream,
1032                 size_t size,
1033                 size_t nmemb,
1034                 void *cls)
1035 {
1036   struct Session *s = cls;
1037   struct HTTP_Client_Plugin *plugin = s->plugin;
1038   struct HTTP_Message *msg = s->msg_head;
1039   size_t len;
1040   char *stat_txt;
1041
1042   if (H_TMP_DISCONNECTING == s->put.state)
1043   {
1044     LOG (GNUNET_ERROR_TYPE_DEBUG,
1045          "Session %p/request %p: disconnect due to inactivity\n",
1046          s, s->put.easyhandle);
1047     return 0;
1048   }
1049
1050   if (NULL == msg)
1051   {
1052     if (GNUNET_YES == plugin->emulate_xhr)
1053     {
1054       LOG (GNUNET_ERROR_TYPE_DEBUG,
1055            "Session %p/request %p: PUT request finished\n",
1056            s,
1057            s->put.easyhandle);
1058       s->put.state = H_TMP_DISCONNECTING;
1059       return 0;
1060     }
1061
1062     /* We have nothing to send, so pause PUT request */
1063     LOG (GNUNET_ERROR_TYPE_DEBUG,
1064          "Session %p/request %p: nothing to send, suspending\n",
1065          s,
1066          s->put.easyhandle);
1067     s->put_disconnect_task = GNUNET_SCHEDULER_add_delayed (PUT_DISCONNECT_TIMEOUT,
1068         &client_put_disconnect, s);
1069     s->put.state = H_PAUSED;
1070     return CURL_READFUNC_PAUSE;
1071   }
1072   /* data to send */
1073   GNUNET_assert (msg->pos < msg->size);
1074   /* calculate how much fits in buffer */
1075   len = GNUNET_MIN (msg->size - msg->pos,
1076                     size * nmemb);
1077   memcpy (stream, &msg->buf[msg->pos], len);
1078   msg->pos += len;
1079   if (msg->pos == msg->size)
1080   {
1081     LOG (GNUNET_ERROR_TYPE_DEBUG,
1082          "Session %p/request %p: sent message with %u bytes sent, removing message from queue\n",
1083          s,
1084          s->put.easyhandle,
1085          msg->size,
1086          msg->pos);
1087     /* Calling transmit continuation  */
1088     GNUNET_CONTAINER_DLL_remove (s->msg_head,
1089                                  s->msg_tail,
1090                                  msg);
1091     GNUNET_assert (0 < s->msgs_in_queue);
1092     s->msgs_in_queue--;
1093     GNUNET_assert (msg->size <= s->bytes_in_queue);
1094     s->bytes_in_queue -= msg->size;
1095     if (NULL != msg->transmit_cont)
1096       msg->transmit_cont (msg->transmit_cont_cls,
1097                           &s->address->peer,
1098                           GNUNET_OK,
1099                           msg->size,
1100                           msg->size + s->overhead);
1101     s->overhead = 0;
1102     GNUNET_free (msg);
1103   }
1104   notify_session_monitor (plugin,
1105                           s,
1106                           GNUNET_TRANSPORT_SS_UPDATE);
1107   GNUNET_asprintf (&stat_txt,
1108                    "# bytes currently in %s_client buffers",
1109                    plugin->protocol);
1110   GNUNET_STATISTICS_update (plugin->env->stats,
1111                             stat_txt,
1112                             - len,
1113                             GNUNET_NO);
1114   GNUNET_free (stat_txt);
1115   GNUNET_asprintf (&stat_txt,
1116                    "# bytes transmitted via %s_client",
1117                    plugin->protocol);
1118   GNUNET_STATISTICS_update (plugin->env->stats,
1119                             stat_txt,
1120                             len,
1121                             GNUNET_NO);
1122   GNUNET_free (stat_txt);
1123   return len;
1124 }
1125
1126
1127 /**
1128  * Wake up a curl handle which was suspended
1129  *
1130  * @param cls the session
1131  * @param tc task context
1132  */
1133 static void
1134 client_wake_up (void *cls,
1135                 const struct GNUNET_SCHEDULER_TaskContext *tc)
1136 {
1137   struct Session *s = cls;
1138
1139   s->recv_wakeup_task = NULL;
1140   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1141     return;
1142   LOG (GNUNET_ERROR_TYPE_DEBUG,
1143        "Session %p/request %p: Waking up GET handle\n",
1144        s, s->get.easyhandle);
1145   if (H_PAUSED == s->put.state)
1146   {
1147     /* PUT request was paused, unpause */
1148     GNUNET_assert (s->put_disconnect_task != NULL);
1149     GNUNET_SCHEDULER_cancel (s->put_disconnect_task);
1150     s->put_disconnect_task = NULL;
1151     s->put.state = H_CONNECTED;
1152     if (NULL != s->put.easyhandle)
1153       curl_easy_pause (s->put.easyhandle, CURLPAUSE_CONT);
1154   }
1155   if (NULL != s->get.easyhandle)
1156     curl_easy_pause (s->get.easyhandle, CURLPAUSE_CONT);
1157 }
1158
1159
1160 /**
1161  * Callback for message stream tokenizer
1162  *
1163  * @param cls the session
1164  * @param client not used
1165  * @param message the message received
1166  * @return always #GNUNET_OK
1167  */
1168 static int
1169 client_receive_mst_cb (void *cls,
1170                        void *client,
1171                        const struct GNUNET_MessageHeader *message)
1172 {
1173   struct Session *s = cls;
1174   struct HTTP_Client_Plugin *plugin;
1175   struct GNUNET_TIME_Relative delay;
1176   char *stat_txt;
1177
1178   plugin = s->plugin;
1179   delay = s->plugin->env->receive (plugin->env->cls,
1180                                    s->address,
1181                                    s,
1182                                    message);
1183   GNUNET_asprintf (&stat_txt,
1184                    "# bytes received via %s_client",
1185                    plugin->protocol);
1186   GNUNET_STATISTICS_update (plugin->env->stats,
1187                             stat_txt,
1188                             ntohs (message->size),
1189                             GNUNET_NO);
1190   GNUNET_free (stat_txt);
1191
1192   s->next_receive = GNUNET_TIME_relative_to_absolute (delay);
1193   if (GNUNET_TIME_absolute_get ().abs_value_us < s->next_receive.abs_value_us)
1194   {
1195     LOG (GNUNET_ERROR_TYPE_DEBUG,
1196          "Client: peer `%s' address `%s' next read delayed for %s\n",
1197          GNUNET_i2s (&s->address->peer),
1198          http_common_plugin_address_to_string (s->plugin->protocol,
1199                                                s->address->address,
1200                                                s->address->address_length),
1201          GNUNET_STRINGS_relative_time_to_string (delay,
1202                                                  GNUNET_YES));
1203   }
1204   client_reschedule_session_timeout (s);
1205   return GNUNET_OK;
1206 }
1207
1208
1209 /**
1210  * Callback method used with libcurl when data for a PUT request are
1211  * received.  We do not expect data here, so we just discard it.
1212  *
1213  * @param stream pointer where to write data
1214  * @param size size of an individual element
1215  * @param nmemb count of elements that can be written to the buffer
1216  * @param cls destination pointer, passed to the libcurl handle
1217  * @return bytes read from stream
1218  */
1219 static size_t
1220 client_receive_put (void *stream,
1221                     size_t size,
1222                     size_t nmemb,
1223                     void *cls)
1224 {
1225   return size * nmemb;
1226 }
1227
1228
1229 /**
1230  * Callback method used with libcurl when data for a GET request are
1231  * received. Forward to MST
1232  *
1233  * @param stream pointer where to write data
1234  * @param size size of an individual element
1235  * @param nmemb count of elements that can be written to the buffer
1236  * @param cls destination pointer, passed to the libcurl handle
1237  * @return bytes read from stream
1238  */
1239 static size_t
1240 client_receive (void *stream,
1241                 size_t size,
1242                 size_t nmemb,
1243                 void *cls)
1244 {
1245   struct Session *s = cls;
1246   struct GNUNET_TIME_Absolute now;
1247   size_t len = size * nmemb;
1248
1249   LOG (GNUNET_ERROR_TYPE_DEBUG,
1250        "Session %p / request %p: Received %u bytes from peer `%s'\n",
1251        s,
1252        s->get.easyhandle,
1253        len,
1254        GNUNET_i2s (&s->address->peer));
1255   now = GNUNET_TIME_absolute_get ();
1256   if (now.abs_value_us < s->next_receive.abs_value_us)
1257   {
1258     struct GNUNET_TIME_Absolute now = GNUNET_TIME_absolute_get ();
1259     struct GNUNET_TIME_Relative delta
1260       = GNUNET_TIME_absolute_get_difference (now, s->next_receive);
1261
1262     LOG (GNUNET_ERROR_TYPE_DEBUG,
1263          "Session %p / request %p: No inbound bandwidth available! Next read was delayed for %s\n",
1264          s,
1265          s->get.easyhandle,
1266          GNUNET_STRINGS_relative_time_to_string (delta,
1267                                                  GNUNET_YES));
1268     if (s->recv_wakeup_task != NULL)
1269     {
1270       GNUNET_SCHEDULER_cancel (s->recv_wakeup_task);
1271       s->recv_wakeup_task = NULL;
1272     }
1273     s->recv_wakeup_task
1274       = GNUNET_SCHEDULER_add_delayed (delta,
1275                                       &client_wake_up,
1276                                       s);
1277     return CURL_WRITEFUNC_PAUSE;
1278   }
1279   if (NULL == s->msg_tk)
1280     s->msg_tk = GNUNET_SERVER_mst_create (&client_receive_mst_cb,
1281                                           s);
1282   GNUNET_SERVER_mst_receive (s->msg_tk,
1283                              s,
1284                              stream,
1285                              len,
1286                              GNUNET_NO,
1287                              GNUNET_NO);
1288   return len;
1289 }
1290
1291
1292 /**
1293  * Task performing curl operations
1294  *
1295  * @param cls plugin as closure
1296  * @param tc scheduler task context
1297  */
1298 static void
1299 client_run (void *cls,
1300             const struct GNUNET_SCHEDULER_TaskContext *tc)
1301 {
1302   struct HTTP_Client_Plugin *plugin = cls;
1303   int running;
1304   long http_statuscode;
1305   CURLMcode mret;
1306   CURLMsg *msg;
1307   int put_request; /* GNUNET_YES if easy handle is put, GNUNET_NO for get */
1308   int msgs_left;
1309
1310   plugin->client_perform_task = NULL;
1311   if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
1312     return;
1313
1314   /* While data are available or timeouts occured */
1315   do
1316   {
1317     running = 0;
1318     /* Perform operations for all handles */
1319     mret = curl_multi_perform (plugin->curl_multi_handle, &running);
1320
1321     /* Get additional information for all handles */
1322     while (NULL != (msg = curl_multi_info_read (plugin->curl_multi_handle, &msgs_left)))
1323     {
1324       CURL *easy_h = msg->easy_handle;
1325       struct Session *s = NULL;
1326       char *d = NULL; /* curl requires 'd' to be a 'char *' */
1327
1328       GNUNET_assert (NULL != easy_h);
1329
1330       /* Obtain session from easy handle */
1331       GNUNET_assert (CURLE_OK == curl_easy_getinfo (easy_h, CURLINFO_PRIVATE, &d));
1332       s = (struct Session *) d;
1333       GNUNET_assert (NULL != s);
1334
1335       if (msg->msg != CURLMSG_DONE)
1336         continue; /* This should not happen */
1337
1338       /* Get HTTP response code */
1339       GNUNET_break (CURLE_OK == curl_easy_getinfo (easy_h,
1340           CURLINFO_RESPONSE_CODE, &http_statuscode));
1341
1342       if (easy_h == s->put.easyhandle)
1343         put_request = GNUNET_YES;
1344       else
1345         put_request = GNUNET_NO;
1346
1347       /* Log status of terminated request */
1348       if  ((0 != msg->data.result) || (http_statuscode != 200))
1349         LOG (GNUNET_ERROR_TYPE_DEBUG,
1350              "Session %p/request %p: %s request to `%s' ended with status %i reason %i: `%s'\n",
1351              s, msg->easy_handle,
1352              (GNUNET_YES == put_request) ? "PUT" : "GET",
1353              GNUNET_i2s (&s->address->peer),
1354              http_statuscode,
1355              msg->data.result,
1356              curl_easy_strerror (msg->data.result));
1357       else
1358         LOG (GNUNET_ERROR_TYPE_DEBUG,
1359              "Session %p/request %p: %s request to `%s' ended normal\n",
1360              s, msg->easy_handle,
1361              (GNUNET_YES == put_request) ? "PUT" : "GET",
1362              GNUNET_i2s (&s->address->peer));
1363
1364       /* Remove easy handle from multi handle */
1365       curl_multi_remove_handle (plugin->curl_multi_handle, easy_h);
1366
1367       /* Clean up easy handle */
1368       curl_easy_cleanup (easy_h);
1369
1370       /* Remove information */
1371       GNUNET_assert (plugin->cur_requests > 0);
1372       plugin->cur_requests--;
1373       LOG  (GNUNET_ERROR_TYPE_INFO,
1374           "%s request to %s done, number of requests decreased to %u\n",
1375           (GNUNET_YES == put_request) ? "PUT" : "GET",
1376           s->url,
1377           plugin->cur_requests);
1378
1379       if (GNUNET_YES == put_request)
1380       {
1381         /* Clean up a PUT request */
1382         s->put.easyhandle = NULL;
1383         s->put.s = NULL;
1384
1385         switch (s->put.state) {
1386           case H_NOT_CONNECTED:
1387           case H_DISCONNECTED:
1388           case H_TMP_DISCONNECTED:
1389             /* This must not happen */
1390             GNUNET_break (0);
1391             break;
1392           case H_TMP_RECONNECT_REQUIRED:
1393             /* Transport called send while disconnect in progess, reconnect */
1394             if (GNUNET_SYSERR == client_connect_put (s))
1395             {
1396               /* Reconnect failed, disconnect session */
1397               http_client_plugin_session_disconnect (plugin, s);
1398             }
1399             break;
1400           case H_TMP_DISCONNECTING:
1401             /* PUT gets temporarily disconnected */
1402             s->put.state = H_TMP_DISCONNECTED;
1403             break;
1404           case H_PAUSED:
1405           case H_CONNECTED:
1406             /* PUT gets permanently disconnected */
1407             s->put.state = H_DISCONNECTED;
1408             http_client_plugin_session_disconnect (plugin, s);
1409             break;
1410           default:
1411             GNUNET_break (0);
1412             break;
1413         }
1414       }
1415       else if (GNUNET_NO == put_request)
1416       {
1417         /* Clean up a GET request */
1418         s->get.easyhandle = NULL;
1419         s->get.s = NULL;
1420
1421         /* If we are emulating an XHR client we need to make another GET
1422          * request.
1423          */
1424         if (GNUNET_YES == plugin->emulate_xhr)
1425         {
1426           if (GNUNET_SYSERR == client_connect_get (s))
1427             http_client_plugin_session_disconnect (plugin, s);
1428         }
1429         else
1430         {
1431           /* GET request was terminated, so disconnect session */
1432           http_client_plugin_session_disconnect (plugin, s);
1433         }
1434       }
1435       else
1436         GNUNET_break (0); /* Must not happen */
1437
1438       GNUNET_STATISTICS_set (plugin->env->stats,
1439                              HTTP_STAT_STR_CONNECTIONS,
1440                              plugin->cur_requests,
1441                              GNUNET_NO);
1442     }
1443   }
1444   while (mret == CURLM_CALL_MULTI_PERFORM);
1445   client_schedule (plugin, GNUNET_NO);
1446 }
1447
1448
1449 #ifdef TCP_STEALTH
1450 /**
1451  * Open TCP socket with TCP STEALTH enabled.
1452  *
1453  * @param clientp our `struct Session *`
1454  * @param purpose why does curl want to open a socket
1455  * @param address what kind of socket does curl want to have opened?
1456  * @return opened socket
1457  */
1458 static curl_socket_t
1459 open_tcp_stealth_socket_cb (void *clientp,
1460                             curlsocktype purpose,
1461                             struct curl_sockaddr *address)
1462 {
1463   struct Session *s = clientp;
1464   int ret;
1465
1466   switch (purpose)
1467   {
1468   case CURLSOCKTYPE_IPCXN:
1469     ret = socket (address->family,
1470                   address->socktype,
1471                   address->protocol);
1472     if (-1 == ret)
1473       return CURL_SOCKET_BAD;
1474     if ( ( (SOCK_STREAM != address->socktype) ||
1475            ( (0 != address->protocol) &&
1476              (IPPROTO_TCP != address->protocol))) )
1477       return (curl_socket_t) ret;
1478     if ( (0 != setsockopt (ret,
1479                            IPPROTO_TCP,
1480                            TCP_STEALTH,
1481                            &s->address->peer,
1482                            sizeof (struct GNUNET_PeerIdentity))) )
1483     {
1484       GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
1485                   _("TCP_STEALTH not supported on this platform.\n"));
1486       (void) close (ret);
1487       return CURL_SOCKET_BAD;
1488     }
1489     return (curl_socket_t) ret;
1490   case CURLSOCKTYPE_ACCEPT:
1491     GNUNET_break (0);
1492     return CURL_SOCKET_BAD;
1493     break;
1494   case CURLSOCKTYPE_LAST:
1495     GNUNET_break (0);
1496     return CURL_SOCKET_BAD;
1497   default:
1498     GNUNET_break (0);
1499     return CURL_SOCKET_BAD;
1500   }
1501 }
1502 #endif
1503
1504
1505 /**
1506  * Connect GET request for a session
1507  *
1508  * @param s the session to connect
1509  * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
1510  */
1511 static int
1512 client_connect_get (struct Session *s)
1513 {
1514   CURLMcode mret;
1515   struct HttpAddress *ha;
1516   uint32_t options;
1517
1518   ha = (struct HttpAddress *) s->address->address;
1519   options = ntohl (ha->options);
1520   /* create get request */
1521   s->get.easyhandle = curl_easy_init ();
1522   s->get.s = s;
1523   if (0 != (options & HTTP_OPTIONS_TCP_STEALTH))
1524   {
1525 #ifdef TCP_STEALTH
1526     curl_easy_setopt (s->get.easyhandle,
1527                       CURLOPT_OPENSOCKETFUNCTION,
1528                       &open_tcp_stealth_socket_cb);
1529     curl_easy_setopt (s->get.easyhandle,
1530                       CURLOPT_OPENSOCKETDATA,
1531                       s);
1532 #else
1533     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1534                 "Cannot connect, TCP STEALTH needed and not supported by kernel.\n");
1535     curl_easy_cleanup (s->get.easyhandle);
1536     s->get.easyhandle = NULL;
1537     s->get.s = NULL;
1538     return GNUNET_SYSERR;
1539 #endif
1540   }
1541
1542 #if VERBOSE_CURL
1543   curl_easy_setopt (s->get.easyhandle,
1544                     CURLOPT_VERBOSE,
1545                     1L);
1546   curl_easy_setopt (s->get.easyhandle,
1547                     CURLOPT_DEBUGFUNCTION,
1548                     &client_log);
1549   curl_easy_setopt (s->get.easyhandle,
1550                     CURLOPT_DEBUGDATA,
1551                     &s->get);
1552 #endif
1553 #if BUILD_HTTPS
1554   curl_easy_setopt (s->get.easyhandle, CURLOPT_SSLVERSION, CURL_SSLVERSION_TLSv1);
1555   {
1556     if (HTTP_OPTIONS_VERIFY_CERTIFICATE ==
1557         (options & HTTP_OPTIONS_VERIFY_CERTIFICATE))
1558     {
1559       curl_easy_setopt (s->get.easyhandle,
1560                         CURLOPT_SSL_VERIFYPEER, 1L);
1561       curl_easy_setopt (s->get.easyhandle,
1562                         CURLOPT_SSL_VERIFYHOST,
1563                         2L);
1564     }
1565     else
1566     {
1567       curl_easy_setopt (s->get.easyhandle,
1568                         CURLOPT_SSL_VERIFYPEER,
1569                         0L);
1570       curl_easy_setopt (s->get.easyhandle,
1571                         CURLOPT_SSL_VERIFYHOST,
1572                         0L);
1573     }
1574   }
1575   curl_easy_setopt (s->get.easyhandle,
1576                     CURLOPT_PROTOCOLS,
1577                     CURLPROTO_HTTPS);
1578   curl_easy_setopt (s->get.easyhandle,
1579                     CURLOPT_REDIR_PROTOCOLS,
1580                     CURLPROTO_HTTPS);
1581 #else
1582   curl_easy_setopt (s->get.easyhandle,
1583                     CURLOPT_PROTOCOLS,
1584                     CURLPROTO_HTTP);
1585   curl_easy_setopt (s->get.easyhandle,
1586                     CURLOPT_REDIR_PROTOCOLS,
1587                     CURLPROTO_HTTP);
1588 #endif
1589
1590   if (NULL != s->plugin->proxy_hostname)
1591   {
1592     curl_easy_setopt (s->get.easyhandle,
1593                       CURLOPT_PROXY,
1594                       s->plugin->proxy_hostname);
1595     curl_easy_setopt (s->get.easyhandle,
1596                       CURLOPT_PROXYTYPE,
1597                       s->plugin->proxytype);
1598     if (NULL != s->plugin->proxy_username)
1599       curl_easy_setopt (s->get.easyhandle,
1600                         CURLOPT_PROXYUSERNAME,
1601                         s->plugin->proxy_username);
1602     if (NULL != s->plugin->proxy_password)
1603       curl_easy_setopt (s->get.easyhandle,
1604                         CURLOPT_PROXYPASSWORD,
1605                         s->plugin->proxy_password);
1606     if (GNUNET_YES == s->plugin->proxy_use_httpproxytunnel)
1607       curl_easy_setopt (s->get.easyhandle,
1608                         CURLOPT_HTTPPROXYTUNNEL,
1609                         s->plugin->proxy_use_httpproxytunnel);
1610   }
1611
1612   if (GNUNET_YES == s->plugin->emulate_xhr)
1613   {
1614     char *url;
1615
1616     GNUNET_asprintf (&url,
1617                      "%s,1",
1618                      s->url);
1619     curl_easy_setopt (s->get.easyhandle,
1620                       CURLOPT_URL,
1621                       url);
1622     GNUNET_free(url);
1623   }
1624   else
1625   {
1626     curl_easy_setopt (s->get.easyhandle,
1627                       CURLOPT_URL,
1628                       s->url);
1629   }
1630   curl_easy_setopt (s->get.easyhandle,
1631                     CURLOPT_READFUNCTION,
1632                     &client_send_cb);
1633   curl_easy_setopt (s->get.easyhandle,
1634                     CURLOPT_READDATA,
1635                     s);
1636   curl_easy_setopt (s->get.easyhandle,
1637                     CURLOPT_WRITEFUNCTION,
1638                     &client_receive);
1639   curl_easy_setopt (s->get.easyhandle,
1640                     CURLOPT_WRITEDATA,
1641                     s);
1642   /* No timeout by default, timeout done with session timeout */
1643   curl_easy_setopt (s->get.easyhandle,
1644                     CURLOPT_TIMEOUT,
1645                     0L);
1646   curl_easy_setopt (s->get.easyhandle,
1647                     CURLOPT_PRIVATE, s);
1648   curl_easy_setopt (s->get.easyhandle,
1649                     CURLOPT_CONNECTTIMEOUT_MS,
1650                     (long) (HTTP_CLIENT_NOT_VALIDATED_TIMEOUT.rel_value_us / 1000LL));
1651   curl_easy_setopt (s->get.easyhandle, CURLOPT_BUFFERSIZE,
1652                     2 * GNUNET_SERVER_MAX_MESSAGE_SIZE);
1653 #if CURL_TCP_NODELAY
1654   curl_easy_setopt (ps->recv_endpoint,
1655                     CURLOPT_TCP_NODELAY,
1656                     1L);
1657 #endif
1658   curl_easy_setopt (s->get.easyhandle,
1659                     CURLOPT_FOLLOWLOCATION,
1660                     0L);
1661
1662   mret = curl_multi_add_handle (s->plugin->curl_multi_handle,
1663                                 s->get.easyhandle);
1664   if (CURLM_OK != mret)
1665   {
1666     LOG (GNUNET_ERROR_TYPE_ERROR,
1667          "Session %p : Failed to add GET handle to multihandle: `%s'\n",
1668          s,
1669          curl_multi_strerror (mret));
1670     curl_easy_cleanup (s->get.easyhandle);
1671     s->get.easyhandle = NULL;
1672     s->get.s = NULL;
1673     GNUNET_break (0);
1674     return GNUNET_SYSERR;
1675   }
1676   s->plugin->cur_requests++;
1677   LOG (GNUNET_ERROR_TYPE_INFO,
1678        "GET request `%s' established, number of requests increased to %u\n",
1679        s->url,
1680        s->plugin->cur_requests);
1681   return GNUNET_OK;
1682 }
1683
1684
1685 /**
1686  * Connect a HTTP put request
1687  *
1688  * @param s the session to connect
1689  * @return #GNUNET_SYSERR for hard failure, #GNUNET_OK for ok
1690  */
1691 static int
1692 client_connect_put (struct Session *s)
1693 {
1694   CURLMcode mret;
1695   struct HttpAddress *ha;
1696   uint32_t options;
1697
1698   ha = (struct HttpAddress *) s->address->address;
1699   options = ntohl (ha->options);
1700   /* create put request */
1701   LOG (GNUNET_ERROR_TYPE_DEBUG,
1702        "Session %p: Init PUT handle\n",
1703        s);
1704   s->put.easyhandle = curl_easy_init ();
1705   s->put.s = s;
1706 #if VERBOSE_CURL
1707   curl_easy_setopt (s->put.easyhandle,
1708                     CURLOPT_VERBOSE,
1709                     1L);
1710   curl_easy_setopt (s->put.easyhandle,
1711                     CURLOPT_DEBUGFUNCTION,
1712                     &client_log);
1713   curl_easy_setopt (s->put.easyhandle,
1714                     CURLOPT_DEBUGDATA,
1715                     &s->put);
1716 #endif
1717   if (0 != (options & HTTP_OPTIONS_TCP_STEALTH))
1718   {
1719 #ifdef TCP_STEALTH
1720     curl_easy_setopt (s->put.easyhandle,
1721                       CURLOPT_OPENSOCKETFUNCTION,
1722                       &open_tcp_stealth_socket_cb);
1723     curl_easy_setopt (s->put.easyhandle,
1724                       CURLOPT_OPENSOCKETDATA,
1725                       s);
1726 #else
1727     GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1728                 "Cannot connect, TCP STEALTH needed and not supported by kernel.\n");
1729     curl_easy_cleanup (s->put.easyhandle);
1730     s->put.easyhandle = NULL;
1731     s->put.s = NULL;
1732     s->put.state = H_DISCONNECTED;
1733     return GNUNET_SYSERR;
1734 #endif
1735   }
1736 #if BUILD_HTTPS
1737   curl_easy_setopt (s->put.easyhandle,
1738                     CURLOPT_SSLVERSION,
1739                     CURL_SSLVERSION_TLSv1);
1740   {
1741     struct HttpAddress *ha;
1742     ha = (struct HttpAddress *) s->address->address;
1743
1744     if (HTTP_OPTIONS_VERIFY_CERTIFICATE ==
1745         (ntohl (ha->options) & HTTP_OPTIONS_VERIFY_CERTIFICATE))
1746     {
1747       curl_easy_setopt (s->put.easyhandle,
1748                         CURLOPT_SSL_VERIFYPEER,
1749                         1L);
1750       curl_easy_setopt (s->put.easyhandle,
1751                         CURLOPT_SSL_VERIFYHOST,
1752                         2L);
1753     }
1754     else
1755     {
1756       curl_easy_setopt (s->put.easyhandle,
1757                         CURLOPT_SSL_VERIFYPEER,
1758                         0L);
1759       curl_easy_setopt (s->put.easyhandle,
1760                         CURLOPT_SSL_VERIFYHOST,
1761                         0L);
1762     }
1763   }
1764   curl_easy_setopt (s->put.easyhandle,
1765                     CURLOPT_PROTOCOLS,
1766                     CURLPROTO_HTTPS);
1767   curl_easy_setopt (s->put.easyhandle,
1768                     CURLOPT_REDIR_PROTOCOLS,
1769                     CURLPROTO_HTTPS);
1770 #else
1771   curl_easy_setopt (s->put.easyhandle,
1772                     CURLOPT_PROTOCOLS,
1773                     CURLPROTO_HTTP);
1774   curl_easy_setopt (s->put.easyhandle,
1775                     CURLOPT_REDIR_PROTOCOLS,
1776                     CURLPROTO_HTTP);
1777 #endif
1778   if (NULL != s->plugin->proxy_hostname)
1779   {
1780     curl_easy_setopt (s->put.easyhandle,
1781                       CURLOPT_PROXY,
1782                       s->plugin->proxy_hostname);
1783     curl_easy_setopt (s->put.easyhandle,
1784                       CURLOPT_PROXYTYPE,
1785                       s->plugin->proxytype);
1786     if (NULL != s->plugin->proxy_username)
1787       curl_easy_setopt (s->put.easyhandle,
1788                         CURLOPT_PROXYUSERNAME,
1789                         s->plugin->proxy_username);
1790     if (NULL != s->plugin->proxy_password)
1791       curl_easy_setopt (s->put.easyhandle,
1792                         CURLOPT_PROXYPASSWORD,
1793                         s->plugin->proxy_password);
1794     if (GNUNET_YES == s->plugin->proxy_use_httpproxytunnel)
1795       curl_easy_setopt (s->put.easyhandle,
1796                         CURLOPT_HTTPPROXYTUNNEL,
1797                         s->plugin->proxy_use_httpproxytunnel);
1798   }
1799
1800   curl_easy_setopt (s->put.easyhandle,
1801                     CURLOPT_URL,
1802                     s->url);
1803   curl_easy_setopt (s->put.easyhandle,
1804                     CURLOPT_UPLOAD,
1805                     1L);
1806   curl_easy_setopt (s->put.easyhandle,
1807                     CURLOPT_READFUNCTION,
1808                     &client_send_cb);
1809   curl_easy_setopt (s->put.easyhandle,
1810                     CURLOPT_READDATA,
1811                     s);
1812   curl_easy_setopt (s->put.easyhandle,
1813                     CURLOPT_WRITEFUNCTION,
1814                     &client_receive_put);
1815   curl_easy_setopt (s->put.easyhandle,
1816                     CURLOPT_WRITEDATA,
1817                     s);
1818   /* No timeout by default, timeout done with session timeout */
1819   curl_easy_setopt (s->put.easyhandle,
1820                     CURLOPT_TIMEOUT,
1821                     0L);
1822   curl_easy_setopt (s->put.easyhandle,
1823                     CURLOPT_PRIVATE,
1824                     s);
1825   curl_easy_setopt (s->put.easyhandle,
1826                     CURLOPT_CONNECTTIMEOUT_MS,
1827                     (long) (HTTP_CLIENT_NOT_VALIDATED_TIMEOUT.rel_value_us / 1000LL));
1828   curl_easy_setopt (s->put.easyhandle, CURLOPT_BUFFERSIZE,
1829                     2 * GNUNET_SERVER_MAX_MESSAGE_SIZE);
1830 #if CURL_TCP_NODELAY
1831   curl_easy_setopt (s->put.easyhandle, CURLOPT_TCP_NODELAY, 1);
1832 #endif
1833   mret = curl_multi_add_handle (s->plugin->curl_multi_handle,
1834                                 s->put.easyhandle);
1835   if (CURLM_OK != mret)
1836   {
1837     LOG (GNUNET_ERROR_TYPE_ERROR,
1838          "Session %p : Failed to add PUT handle to multihandle: `%s'\n",
1839          s, curl_multi_strerror (mret));
1840     curl_easy_cleanup (s->put.easyhandle);
1841     s->put.easyhandle = NULL;
1842     s->put.s = NULL;
1843     s->put.state = H_DISCONNECTED;
1844     return GNUNET_SYSERR;
1845   }
1846   s->put.state = H_CONNECTED;
1847   s->plugin->cur_requests++;
1848
1849   LOG  (GNUNET_ERROR_TYPE_INFO,
1850       "PUT request `%s' established, number of requests increased to %u\n",
1851       s->url, s->plugin->cur_requests);
1852
1853   return GNUNET_OK;
1854 }
1855
1856
1857 /**
1858  * Connect both PUT and GET request for a session
1859  *
1860  * @param s the session to connect
1861  * @return #GNUNET_OK on success, #GNUNET_SYSERR otherwise
1862  */
1863 static int
1864 client_connect (struct Session *s)
1865 {
1866   struct HTTP_Client_Plugin *plugin = s->plugin;
1867   int res = GNUNET_OK;
1868
1869   /* create url */
1870   if (NULL ==
1871       http_common_plugin_address_to_string(plugin->protocol,
1872                                            s->address->address,
1873                                            s->address->address_length))
1874   {
1875     LOG (GNUNET_ERROR_TYPE_DEBUG,
1876          "Invalid address peer `%s'\n",
1877          GNUNET_i2s(&s->address->peer));
1878     return GNUNET_SYSERR;
1879   }
1880
1881   GNUNET_asprintf (&s->url,
1882                    "%s/%s;%u",
1883                    http_common_plugin_address_to_url (NULL,
1884                                                       s->address->address,
1885                                                       s->address->address_length),
1886                    GNUNET_i2s_full (plugin->env->my_identity),
1887                    plugin->last_tag);
1888
1889   plugin->last_tag++;
1890   LOG (GNUNET_ERROR_TYPE_DEBUG,
1891        "Initiating outbound session peer `%s' using address `%s'\n",
1892        GNUNET_i2s (&s->address->peer), s->url);
1893
1894   if (GNUNET_SYSERR == client_connect_get (s))
1895     return GNUNET_SYSERR;
1896   /* If we are emulating an XHR client then delay sending a PUT request until
1897    * there is something to send.
1898    */
1899   if (GNUNET_YES == plugin->emulate_xhr)
1900   {
1901     s->put.state = H_TMP_DISCONNECTED;
1902   }
1903   else if (GNUNET_SYSERR == client_connect_put (s))
1904     return GNUNET_SYSERR;
1905
1906   LOG (GNUNET_ERROR_TYPE_DEBUG,
1907        "Session %p: connected with GET %p and PUT %p\n",
1908        s, s->get.easyhandle,
1909        s->put.easyhandle);
1910   /* Perform connect */
1911   GNUNET_STATISTICS_set (plugin->env->stats,
1912                          HTTP_STAT_STR_CONNECTIONS,
1913                          plugin->cur_requests,
1914                          GNUNET_NO);
1915   /* Re-schedule since handles have changed */
1916   if (NULL != plugin->client_perform_task)
1917   {
1918     GNUNET_SCHEDULER_cancel (plugin->client_perform_task);
1919     plugin->client_perform_task = NULL;
1920   }
1921
1922   /* Schedule task to run immediately */
1923   plugin->client_perform_task = GNUNET_SCHEDULER_add_now (client_run,
1924                                                           plugin);
1925   return res;
1926 }
1927
1928
1929 /**
1930  * Function obtain the network type for a session
1931  *
1932  * @param cls closure (`struct Plugin*`)
1933  * @param session the session
1934  * @return the network type
1935  */
1936 static enum GNUNET_ATS_Network_Type
1937 http_client_plugin_get_network (void *cls,
1938                                 struct Session *session)
1939 {
1940   return session->scope;
1941 }
1942
1943
1944 /**
1945  * Function obtain the network type for an address.
1946  *
1947  * @param cls closure (`struct Plugin *`)
1948  * @param address the address
1949  * @return the network type
1950  */
1951 static enum GNUNET_ATS_Network_Type
1952 http_client_plugin_get_network_for_address (void *cls,
1953                                             const struct GNUNET_HELLO_Address *address)
1954 {
1955   struct HTTP_Client_Plugin *plugin = cls;
1956
1957   return http_common_get_network_for_address (plugin->env,
1958                                               address);
1959 }
1960
1961
1962 /**
1963  * Session was idle, so disconnect it
1964  *
1965  * @param cls the `struct Session` of the idle session
1966  * @param tc scheduler context
1967  */
1968 static void
1969 client_session_timeout (void *cls,
1970                         const struct GNUNET_SCHEDULER_TaskContext *tc)
1971 {
1972   struct Session *s = cls;
1973   struct GNUNET_TIME_Relative left;
1974
1975   s->timeout_task = NULL;
1976   left = GNUNET_TIME_absolute_get_remaining (s->timeout);
1977   if (0 != left.rel_value_us)
1978   {
1979     /* not actually our turn yet, but let's at least update
1980        the monitor, it may think we're about to die ... */
1981     notify_session_monitor (s->plugin,
1982                             s,
1983                             GNUNET_TRANSPORT_SS_UPDATE);
1984     s->timeout_task = GNUNET_SCHEDULER_add_delayed (left,
1985                                                     &client_session_timeout,
1986                                                     s);
1987     return;
1988   }
1989   LOG (TIMEOUT_LOG,
1990        "Session %p was idle for %s, disconnecting\n",
1991        s,
1992        GNUNET_STRINGS_relative_time_to_string (HTTP_CLIENT_SESSION_TIMEOUT,
1993                                                GNUNET_YES));
1994   GNUNET_assert (GNUNET_OK ==
1995                  http_client_plugin_session_disconnect (s->plugin,
1996                                                  s));
1997 }
1998
1999
2000 /**
2001  * Creates a new outbound session the transport service will use to
2002  * send data to the peer
2003  *
2004  * @param cls the plugin
2005  * @param address the address
2006  * @return the session or NULL of max connections exceeded
2007  */
2008 static struct Session *
2009 http_client_plugin_get_session (void *cls,
2010                                 const struct GNUNET_HELLO_Address *address)
2011 {
2012   struct HTTP_Client_Plugin *plugin = cls;
2013   struct Session *s;
2014   struct sockaddr *sa;
2015   enum GNUNET_ATS_Network_Type net_type;
2016   size_t salen = 0;
2017   int res;
2018
2019   GNUNET_assert (NULL != address->address);
2020
2021   /* find existing session */
2022   s = client_lookup_session (plugin, address);
2023   if (NULL != s)
2024     return s;
2025
2026   /* create a new session */
2027   if (plugin->max_requests <= plugin->cur_requests)
2028   {
2029     LOG (GNUNET_ERROR_TYPE_WARNING,
2030          "Maximum number of requests (%u) reached: "
2031          "cannot connect to peer `%s'\n",
2032          plugin->max_requests,
2033          GNUNET_i2s (&address->peer));
2034     return NULL;
2035   }
2036
2037   /* Determine network location */
2038   net_type = GNUNET_ATS_NET_UNSPECIFIED;
2039   sa = http_common_socket_from_address (address->address,
2040                                         address->address_length,
2041                                         &res);
2042   if (GNUNET_SYSERR == res)
2043     return NULL;
2044   if (GNUNET_YES == res)
2045   {
2046     GNUNET_assert (NULL != sa);
2047     if (AF_INET == sa->sa_family)
2048     {
2049       salen = sizeof (struct sockaddr_in);
2050     }
2051     else if (AF_INET6 == sa->sa_family)
2052     {
2053       salen = sizeof (struct sockaddr_in6);
2054     }
2055     net_type = plugin->env->get_address_type (plugin->env->cls, sa, salen);
2056     GNUNET_free (sa);
2057   }
2058   else if (GNUNET_NO == res)
2059   {
2060     /* Cannot convert to sockaddr -> is external hostname */
2061     net_type = GNUNET_ATS_NET_WAN;
2062   }
2063   if (GNUNET_ATS_NET_UNSPECIFIED == net_type)
2064   {
2065     GNUNET_break (0);
2066     return NULL;
2067   }
2068
2069   s = GNUNET_new (struct Session);
2070   s->plugin = plugin;
2071   s->address = GNUNET_HELLO_address_copy (address);
2072   s->scope = net_type;
2073
2074   s->put.state = H_NOT_CONNECTED;
2075   s->timeout = GNUNET_TIME_relative_to_absolute (HTTP_CLIENT_SESSION_TIMEOUT);
2076   s->timeout_task =  GNUNET_SCHEDULER_add_delayed (HTTP_CLIENT_SESSION_TIMEOUT,
2077                                                    &client_session_timeout,
2078                                                    s);
2079   LOG (GNUNET_ERROR_TYPE_DEBUG,
2080        "Created new session %p for `%s' address `%s''\n",
2081        s,
2082        http_common_plugin_address_to_string (plugin->protocol,
2083                                              s->address->address,
2084                                              s->address->address_length),
2085        GNUNET_i2s (&s->address->peer));
2086
2087   /* add new session */
2088   (void) GNUNET_CONTAINER_multipeermap_put (plugin->sessions,
2089                                             &s->address->peer,
2090                                             s,
2091                                             GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
2092   /* initiate new connection */
2093   if (GNUNET_SYSERR == client_connect (s))
2094   {
2095     LOG (GNUNET_ERROR_TYPE_ERROR,
2096          "Cannot connect to peer `%s' address `%s''\n",
2097          http_common_plugin_address_to_string (plugin->protocol,
2098              s->address->address, s->address->address_length),
2099              GNUNET_i2s (&s->address->peer));
2100     client_delete_session (s);
2101     return NULL;
2102   }
2103   notify_session_monitor (plugin,
2104                           s,
2105                           GNUNET_TRANSPORT_SS_INIT);
2106   notify_session_monitor (plugin,
2107                           s,
2108                           GNUNET_TRANSPORT_SS_UP); /* or handshake? */
2109   return s;
2110 }
2111
2112
2113 /**
2114  * Setup http_client plugin
2115  *
2116  * @param plugin the plugin handle
2117  * @return #GNUNET_OK on success, #GNUNET_SYSERR on error
2118  */
2119 static int
2120 client_start (struct HTTP_Client_Plugin *plugin)
2121 {
2122   curl_global_init (CURL_GLOBAL_ALL);
2123   plugin->curl_multi_handle = curl_multi_init ();
2124
2125   if (NULL == plugin->curl_multi_handle)
2126   {
2127     LOG (GNUNET_ERROR_TYPE_ERROR,
2128          _("Could not initialize curl multi handle, failed to start %s plugin!\n"),
2129          plugin->name);
2130     return GNUNET_SYSERR;
2131   }
2132   return GNUNET_OK;
2133 }
2134
2135
2136 /**
2137  * Another peer has suggested an address for this
2138  * peer and transport plugin.  Check that this could be a valid
2139  * address.  If so, consider adding it to the list
2140  * of addresses.
2141  *
2142  * @param cls closure with the `struct Plugin`
2143  * @param addr pointer to the address
2144  * @param addrlen length of @a addr
2145  * @return #GNUNET_OK if this is a plausible address for this peer
2146  *         and transport; always returns #GNUNET_NO (this is the client!)
2147  */
2148 static int
2149 http_client_plugin_address_suggested (void *cls,
2150                                       const void *addr,
2151                                       size_t addrlen)
2152 {
2153   /* A HTTP/S client does not have any valid address so:*/
2154   return GNUNET_NO;
2155 }
2156
2157
2158 /**
2159  * Exit point from the plugin.
2160  *
2161  * @param cls api as closure
2162  * @return NULL
2163  */
2164 void *
2165 LIBGNUNET_PLUGIN_TRANSPORT_DONE (void *cls)
2166 {
2167   struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
2168   struct HTTP_Client_Plugin *plugin = api->cls;
2169
2170   if (NULL == api->cls)
2171   {
2172     /* Stub shutdown */
2173     GNUNET_free (api);
2174     return NULL;
2175   }
2176   LOG (GNUNET_ERROR_TYPE_DEBUG,
2177        _("Shutting down plugin `%s'\n"),
2178        plugin->name);
2179   GNUNET_CONTAINER_multipeermap_iterate (plugin->sessions,
2180                                          &destroy_session_cb,
2181                                          plugin);
2182   if (NULL != plugin->client_perform_task)
2183   {
2184     GNUNET_SCHEDULER_cancel (plugin->client_perform_task);
2185     plugin->client_perform_task = NULL;
2186   }
2187   if (NULL != plugin->curl_multi_handle)
2188   {
2189     curl_multi_cleanup (plugin->curl_multi_handle);
2190     plugin->curl_multi_handle = NULL;
2191   }
2192   curl_global_cleanup ();
2193   LOG (GNUNET_ERROR_TYPE_DEBUG,
2194        _("Shutdown for plugin `%s' complete\n"),
2195        plugin->name);
2196   GNUNET_CONTAINER_multipeermap_destroy (plugin->sessions);
2197   GNUNET_free_non_null (plugin->proxy_hostname);
2198   GNUNET_free_non_null (plugin->proxy_username);
2199   GNUNET_free_non_null (plugin->proxy_password);
2200   GNUNET_free (plugin);
2201   GNUNET_free (api);
2202   return NULL;
2203 }
2204
2205
2206 /**
2207  * Configure plugin
2208  *
2209  * @param plugin the plugin handle
2210  * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
2211  */
2212 static int
2213 client_configure_plugin (struct HTTP_Client_Plugin *plugin)
2214 {
2215   unsigned long long max_requests;
2216   char *proxy_type;
2217
2218   /* Optional parameters */
2219   if (GNUNET_OK !=
2220       GNUNET_CONFIGURATION_get_value_number (plugin->env->cfg,
2221                                              plugin->name,
2222                                              "MAX_CONNECTIONS",
2223                                              &max_requests))
2224     max_requests = 128;
2225   plugin->max_requests = max_requests;
2226
2227   LOG (GNUNET_ERROR_TYPE_DEBUG,
2228        _("Maximum number of requests is %u\n"),
2229        plugin->max_requests);
2230
2231   /* Read proxy configuration */
2232   if (GNUNET_OK ==
2233       GNUNET_CONFIGURATION_get_value_string (plugin->env->cfg,
2234                                              plugin->name,
2235                                              "PROXY",
2236                                              &plugin->proxy_hostname))
2237   {
2238     LOG (GNUNET_ERROR_TYPE_DEBUG,
2239          "Found proxy host: `%s'\n",
2240          plugin->proxy_hostname);
2241     /* proxy username */
2242     if (GNUNET_OK ==
2243         GNUNET_CONFIGURATION_get_value_string (plugin->env->cfg,
2244                                                plugin->name,
2245                                                "PROXY_USERNAME",
2246                                                &plugin->proxy_username))
2247     {
2248       LOG (GNUNET_ERROR_TYPE_DEBUG,
2249            "Found proxy username name: `%s'\n",
2250            plugin->proxy_username);
2251     }
2252
2253     /* proxy password */
2254     if (GNUNET_OK ==
2255         GNUNET_CONFIGURATION_get_value_string (plugin->env->cfg,
2256                                                plugin->name,
2257                                                "PROXY_PASSWORD",
2258                                                &plugin->proxy_password))
2259     {
2260       LOG (GNUNET_ERROR_TYPE_DEBUG,
2261            "Found proxy password name: `%s'\n",
2262            plugin->proxy_password);
2263     }
2264
2265     /* proxy type */
2266     if (GNUNET_OK ==
2267         GNUNET_CONFIGURATION_get_value_string (plugin->env->cfg,
2268                                                plugin->name,
2269                                                "PROXY_TYPE",
2270                                                &proxy_type))
2271     {
2272       GNUNET_STRINGS_utf8_toupper (proxy_type, proxy_type);
2273
2274       if (0 == strcmp(proxy_type, "HTTP"))
2275         plugin->proxytype = CURLPROXY_HTTP;
2276       else if (0 == strcmp(proxy_type, "SOCKS4"))
2277         plugin->proxytype = CURLPROXY_SOCKS4;
2278       else if (0 == strcmp(proxy_type, "SOCKS5"))
2279         plugin->proxytype = CURLPROXY_SOCKS5;
2280       else if (0 == strcmp(proxy_type, "SOCKS4A"))
2281         plugin->proxytype = CURLPROXY_SOCKS4A;
2282       else if (0 == strcmp(proxy_type, "SOCKS5_HOSTNAME "))
2283         plugin->proxytype = CURLPROXY_SOCKS5_HOSTNAME ;
2284       else
2285       {
2286         LOG (GNUNET_ERROR_TYPE_ERROR,
2287              _("Invalid proxy type: `%s', disabling proxy! Check configuration!\n"),
2288              proxy_type);
2289
2290         GNUNET_free (proxy_type);
2291         GNUNET_free (plugin->proxy_hostname);
2292         plugin->proxy_hostname = NULL;
2293         GNUNET_free_non_null (plugin->proxy_username);
2294         plugin->proxy_username = NULL;
2295         GNUNET_free_non_null (plugin->proxy_password);
2296         plugin->proxy_password = NULL;
2297
2298         return GNUNET_SYSERR;
2299       }
2300
2301       LOG (GNUNET_ERROR_TYPE_DEBUG,
2302            "Found proxy type: `%s'\n",
2303            proxy_type);
2304     }
2305
2306     /* proxy http tunneling */
2307     plugin->proxy_use_httpproxytunnel
2308       = GNUNET_CONFIGURATION_get_value_yesno (plugin->env->cfg,
2309                                               plugin->name,
2310                                               "PROXY_HTTP_TUNNELING");
2311     if (GNUNET_SYSERR == plugin->proxy_use_httpproxytunnel)
2312       plugin->proxy_use_httpproxytunnel = GNUNET_NO;
2313
2314     GNUNET_free_non_null (proxy_type);
2315   }
2316
2317   /* Should we emulate an XHR client for testing? */
2318   plugin->emulate_xhr
2319     = GNUNET_CONFIGURATION_get_value_yesno (plugin->env->cfg,
2320                                             plugin->name,
2321                                             "EMULATE_XHR");
2322   return GNUNET_OK;
2323 }
2324
2325
2326 /**
2327  * Function to convert an address to a human-readable string.
2328  *
2329  * @param cls closure
2330  * @param addr address to convert
2331  * @param addrlen address length
2332  * @return res string if conversion was successful, NULL otherwise
2333  */
2334 static const char *
2335 http_client_plugin_address_to_string (void *cls,
2336                                       const void *addr,
2337                                       size_t addrlen)
2338 {
2339   return http_common_plugin_address_to_string (PLUGIN_NAME,
2340                                                addr,
2341                                                addrlen);
2342 }
2343
2344
2345 /**
2346  * Function that will be called whenever the transport service wants to
2347  * notify the plugin that a session is still active and in use and
2348  * therefore the session timeout for this session has to be updated
2349  *
2350  * @param cls closure
2351  * @param peer which peer was the session for
2352  * @param session which session is being updated
2353  */
2354 static void
2355 http_client_plugin_update_session_timeout (void *cls,
2356                                            const struct GNUNET_PeerIdentity *peer,
2357                                            struct Session *session)
2358 {
2359   client_reschedule_session_timeout (session);
2360 }
2361
2362
2363 /**
2364  * Function that will be called whenever the transport service wants to
2365  * notify the plugin that the inbound quota changed and that the plugin
2366  * should update it's delay for the next receive value
2367  *
2368  * @param cls closure
2369  * @param peer which peer was the session for
2370  * @param s which session is being updated
2371  * @param delay new delay to use for receiving
2372  */
2373 static void
2374 http_client_plugin_update_inbound_delay (void *cls,
2375                                          const struct GNUNET_PeerIdentity *peer,
2376                                          struct Session *s,
2377                                          struct GNUNET_TIME_Relative delay)
2378 {
2379   s->next_receive = GNUNET_TIME_relative_to_absolute (delay);
2380   LOG (GNUNET_ERROR_TYPE_DEBUG,
2381        "New inbound delay %s\n",
2382        GNUNET_STRINGS_relative_time_to_string (delay,
2383                                                GNUNET_NO));
2384   if (s->recv_wakeup_task != NULL)
2385   {
2386     GNUNET_SCHEDULER_cancel (s->recv_wakeup_task);
2387     s->recv_wakeup_task = GNUNET_SCHEDULER_add_delayed (delay,
2388         &client_wake_up, s);
2389   }
2390 }
2391
2392
2393 /**
2394  * Return information about the given session to the
2395  * monitor callback.
2396  *
2397  * @param cls the `struct Plugin` with the monitor callback (`sic`)
2398  * @param peer peer we send information about
2399  * @param value our `struct Session` to send information about
2400  * @return #GNUNET_OK (continue to iterate)
2401  */
2402 static int
2403 send_session_info_iter (void *cls,
2404                         const struct GNUNET_PeerIdentity *peer,
2405                         void *value)
2406 {
2407   struct HTTP_Client_Plugin *plugin = cls;
2408   struct Session *session = value;
2409
2410   notify_session_monitor (plugin,
2411                           session,
2412                           GNUNET_TRANSPORT_SS_INIT);
2413   notify_session_monitor (plugin,
2414                           session,
2415                           GNUNET_TRANSPORT_SS_UP); /* FIXME: or handshake? */
2416   return GNUNET_OK;
2417 }
2418
2419
2420 /**
2421  * Begin monitoring sessions of a plugin.  There can only
2422  * be one active monitor per plugin (i.e. if there are
2423  * multiple monitors, the transport service needs to
2424  * multiplex the generated events over all of them).
2425  *
2426  * @param cls closure of the plugin
2427  * @param sic callback to invoke, NULL to disable monitor;
2428  *            plugin will being by iterating over all active
2429  *            sessions immediately and then enter monitor mode
2430  * @param sic_cls closure for @a sic
2431  */
2432 static void
2433 http_client_plugin_setup_monitor (void *cls,
2434                                   GNUNET_TRANSPORT_SessionInfoCallback sic,
2435                                   void *sic_cls)
2436 {
2437   struct HTTP_Client_Plugin *plugin = cls;
2438
2439   plugin->sic = sic;
2440   plugin->sic_cls = sic_cls;
2441   if (NULL != sic)
2442   {
2443     GNUNET_CONTAINER_multipeermap_iterate (plugin->sessions,
2444                                            &send_session_info_iter,
2445                                            plugin);
2446     /* signal end of first iteration */
2447     sic (sic_cls, NULL, NULL);
2448   }
2449 }
2450
2451
2452 /**
2453  * Entry point for the plugin.
2454  */
2455 void *
2456 LIBGNUNET_PLUGIN_TRANSPORT_INIT (void *cls)
2457 {
2458   struct GNUNET_TRANSPORT_PluginEnvironment *env = cls;
2459   struct GNUNET_TRANSPORT_PluginFunctions *api;
2460   struct HTTP_Client_Plugin *plugin;
2461
2462   if (NULL == env->receive)
2463   {
2464     /* run in 'stub' mode (i.e. as part of gnunet-peerinfo), don't fully
2465        initialze the plugin or the API */
2466     api = GNUNET_new (struct GNUNET_TRANSPORT_PluginFunctions);
2467     api->cls = NULL;
2468     api->address_to_string = &http_client_plugin_address_to_string;
2469     api->string_to_address = &http_common_plugin_string_to_address;
2470     api->address_pretty_printer = &http_common_plugin_address_pretty_printer;
2471     return api;
2472   }
2473
2474   plugin = GNUNET_new (struct HTTP_Client_Plugin);
2475   plugin->env = env;
2476   plugin->sessions = GNUNET_CONTAINER_multipeermap_create (128,
2477                                                            GNUNET_YES);
2478   api = GNUNET_new (struct GNUNET_TRANSPORT_PluginFunctions);
2479   api->cls = plugin;
2480   api->send = &http_client_plugin_send;
2481   api->disconnect_session = &http_client_plugin_session_disconnect;
2482   api->query_keepalive_factor = &http_client_query_keepalive_factor;
2483   api->disconnect_peer = &http_client_plugin_peer_disconnect;
2484   api->check_address = &http_client_plugin_address_suggested;
2485   api->get_session = &http_client_plugin_get_session;
2486   api->address_to_string = &http_client_plugin_address_to_string;
2487   api->string_to_address = &http_common_plugin_string_to_address;
2488   api->address_pretty_printer = &http_common_plugin_address_pretty_printer;
2489   api->get_network = &http_client_plugin_get_network;
2490   api->get_network_for_address = &http_client_plugin_get_network_for_address;
2491   api->update_session_timeout = &http_client_plugin_update_session_timeout;
2492   api->update_inbound_delay = &http_client_plugin_update_inbound_delay;
2493   api->setup_monitor = &http_client_plugin_setup_monitor;
2494 #if BUILD_HTTPS
2495   plugin->name = "transport-https_client";
2496   plugin->protocol = "https";
2497 #else
2498   plugin->name = "transport-http_client";
2499   plugin->protocol = "http";
2500 #endif
2501   plugin->last_tag = 1;
2502
2503   if (GNUNET_SYSERR == client_configure_plugin (plugin))
2504   {
2505     LIBGNUNET_PLUGIN_TRANSPORT_DONE (api);
2506     return NULL;
2507   }
2508
2509   /* Start client */
2510   if (GNUNET_SYSERR == client_start (plugin))
2511   {
2512     LIBGNUNET_PLUGIN_TRANSPORT_DONE (api);
2513     return NULL;
2514   }
2515   return api;
2516 }
2517
2518 /* end of plugin_transport_http_client.c */