libpurple/protocols/jabber/iq.c

   1 /*
   2  * purple - Jabber Protocol Plugin
   3  *
   4  * Purple is the legal property of its developers, whose names are too numerous
   5  * to list here.  Please refer to the COPYRIGHT file distributed with this
   6  * source distribution.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA
  21  *
  22  */
  23 #include "internal.h"
  24 #include "core.h"
  25 #include "debug.h"
  26 #include "prefs.h"
  27 #include "util.h"
  28
  29 #include "buddy.h"
  30 #include "disco.h"
  31 #include "google/gmail.h"
  32 #include "google/google.h"
  33 #include "google/jingleinfo.h"
  34 #include "google/google_session.h"
  35 #include "iq.h"
  36 #include "jingle/jingle.h"
  37 #include "oob.h"
  38 #include "roster.h"
  39 #include "si.h"
  40 #include "ping.h"
  41 #include "adhoccommands.h"
  42 #include "data.h"
  43 #include "ibb.h"
  44
  45 #ifdef _WIN32
  46 #include "utsname.h"
  47 #endif
  48
  49 static GHashTable *iq_handlers = NULL;
  50 static GHashTable *signal_iq_handlers = NULL;
  51
  52 struct _JabberIqCallbackData {
  53         JabberIqCallback *callback;
  54         gpointer data;
  55         JabberID *to;
  56 };
  57
  58 void jabber_iq_callbackdata_free(JabberIqCallbackData *jcd)
  59 {
  60         jabber_id_free(jcd->to);
  61         g_free(jcd);
  62 }
  63
  64 JabberIq *jabber_iq_new(JabberStream *js, JabberIqType type)
  65 {
  66         JabberIq *iq;
  67
  68         iq = g_new0(JabberIq, 1);
  69
  70         iq->type = type;
  71
  72         iq->node = xmlnode_new("iq");
  73         switch(iq->type) {
  74                 case JABBER_IQ_SET:
  75                         xmlnode_set_attrib(iq->node, "type", "set");
  76                         break;
  77                 case JABBER_IQ_GET:
  78                         xmlnode_set_attrib(iq->node, "type", "get");
  79                         break;
  80                 case JABBER_IQ_ERROR:
  81                         xmlnode_set_attrib(iq->node, "type", "error");
  82                         break;
  83                 case JABBER_IQ_RESULT:
  84                         xmlnode_set_attrib(iq->node, "type", "result");
  85                         break;
  86                 case JABBER_IQ_NONE:
  87                         /* this shouldn't ever happen */
  88                         break;
  89         }
  90
  91         iq->js = js;
  92
  93         if(type == JABBER_IQ_GET || type == JABBER_IQ_SET) {
  94                 iq->id = jabber_get_next_id(js);
  95                 xmlnode_set_attrib(iq->node, "id", iq->id);
  96         }
  97
  98         return iq;
  99 }
 100
 101 JabberIq *jabber_iq_new_query(JabberStream *js, JabberIqType type,
 102                 const char *xmlns)
 103 {
 104         JabberIq *iq = jabber_iq_new(js, type);
 105         xmlnode *query;
 106
 107         query = xmlnode_new_child(iq->node, "query");
 108         xmlnode_set_namespace(query, xmlns);
 109
 110         return iq;
 111 }
 112
 113 void
 114 jabber_iq_set_callback(JabberIq *iq, JabberIqCallback *callback, gpointer data)
 115 {
 116         iq->callback = callback;
 117         iq->callback_data = data;
 118 }
 119
 120 void jabber_iq_set_id(JabberIq *iq, const char *id)
 121 {
 122         g_free(iq->id);
 123
 124         if(id) {
 125                 xmlnode_set_attrib(iq->node, "id", id);
 126                 iq->id = g_strdup(id);
 127         } else {
 128                 xmlnode_remove_attrib(iq->node, "id");
 129                 iq->id = NULL;
 130         }
 131 }
 132
 133 void jabber_iq_send(JabberIq *iq)
 134 {
 135         JabberIqCallbackData *jcd;
 136         g_return_if_fail(iq != NULL);
 137
 138         jabber_send(iq->js, iq->node);
 139
 140         if(iq->id && iq->callback) {
 141                 jcd = g_new0(JabberIqCallbackData, 1);
 142                 jcd->callback = iq->callback;
 143                 jcd->data = iq->callback_data;
 144                 jcd->to = jabber_id_new(xmlnode_get_attrib(iq->node, "to"));
 145
 146                 g_hash_table_insert(iq->js->iq_callbacks, g_strdup(iq->id), jcd);
 147         }
 148
 149         jabber_iq_free(iq);
 150 }
 151
 152 void jabber_iq_free(JabberIq *iq)
 153 {
 154         g_return_if_fail(iq != NULL);
 155
 156         g_free(iq->id);
 157         xmlnode_free(iq->node);
 158         g_free(iq);
 159 }
 160
 161 static void jabber_iq_last_parse(JabberStream *js, const char *from,
 162                                  JabberIqType type, const char *id,
 163                                  xmlnode *packet)
 164 {
 165         JabberIq *iq;
 166         xmlnode *query;
 167         char *idle_time;
 168
 169         if(type == JABBER_IQ_GET) {
 170                 iq = jabber_iq_new_query(js, JABBER_IQ_RESULT, NS_LAST_ACTIVITY);
 171                 jabber_iq_set_id(iq, id);
 172                 if (from)
 173                         xmlnode_set_attrib(iq->node, "to", from);
 174
 175                 query = xmlnode_get_child(iq->node, "query");
 176
 177                 idle_time = g_strdup_printf("%ld", js->idle ? time(NULL) - js->idle : 0);
 178                 xmlnode_set_attrib(query, "seconds", idle_time);
 179                 g_free(idle_time);
 180
 181                 jabber_iq_send(iq);
 182         }
 183 }
 184
 185 static void jabber_time_parse(JabberStream *js, const char *from,
 186                               JabberIqType type, const char *id,
 187                               xmlnode *child)
 188 {
 189         JabberIq *iq;
 190         time_t now_t;
 191         struct tm *tm;
 192
 193         time(&now_t);
 194
 195         if(type == JABBER_IQ_GET) {
 196                 xmlnode *tzo, *utc;
 197                 const char *date, *tz;
 198
 199                 iq = jabber_iq_new(js, JABBER_IQ_RESULT);
 200                 jabber_iq_set_id(iq, id);
 201                 if (from)
 202                         xmlnode_set_attrib(iq->node, "to", from);
 203
 204                 child = xmlnode_new_child(iq->node, child->name);
 205                 xmlnode_set_namespace(child, NS_ENTITY_TIME);
 206
 207                 /* <tzo>-06:00</tzo> */
 208                 tm = localtime(&now_t);
 209                 tz = purple_get_tzoff_str(tm, TRUE);
 210                 tzo = xmlnode_new_child(child, "tzo");
 211                 xmlnode_insert_data(tzo, tz, -1);
 212
 213                 /* <utc>2006-12-19T17:58:35Z</utc> */
 214                 tm = gmtime(&now_t);
 215                 date = purple_utf8_strftime("%Y-%m-%dT%H:%M:%SZ", tm);
 216                 utc = xmlnode_new_child(child, "utc");
 217                 xmlnode_insert_data(utc, date, -1);
 218
 219                 jabber_iq_send(iq);
 220         } else {
 221                 /* TODO: Errors */
 222         }
 223 }
 224
 225 static void jabber_iq_version_parse(JabberStream *js, const char *from,
 226                                     JabberIqType type, const char *id,
 227                                     xmlnode *packet)
 228 {
 229         JabberIq *iq;
 230         xmlnode *query;
 231
 232         if(type == JABBER_IQ_GET) {
 233                 GHashTable *ui_info;
 234                 const char *ui_name = NULL, *ui_version = NULL;
 235 #if 0
 236                 char *os = NULL;
 237                 if(!purple_prefs_get_bool("/plugins/prpl/jabber/hide_os")) {
 238                         struct utsname osinfo;
 239
 240                         uname(&osinfo);
 241                         os = g_strdup_printf("%s %s %s", osinfo.sysname, osinfo.release,
 242                                         osinfo.machine);
 243                 }
 244 #endif
 245
 246                 iq = jabber_iq_new_query(js, JABBER_IQ_RESULT, "jabber:iq:version");
 247                 if (from)
 248                         xmlnode_set_attrib(iq->node, "to", from);
 249                 jabber_iq_set_id(iq, id);
 250
 251                 query = xmlnode_get_child(iq->node, "query");
 252
 253                 ui_info = purple_core_get_ui_info();
 254
 255                 if(NULL != ui_info) {
 256                         ui_name = g_hash_table_lookup(ui_info, "name");
 257                         ui_version = g_hash_table_lookup(ui_info, "version");
 258                 }
 259
 260                 if(NULL != ui_name && NULL != ui_version) {
 261                         char *version_complete = g_strdup_printf("%s (libpurple " VERSION ")", ui_version);
 262                         xmlnode_insert_data(xmlnode_new_child(query, "name"), ui_name, -1);
 263                         xmlnode_insert_data(xmlnode_new_child(query, "version"), version_complete, -1);
 264                         g_free(version_complete);
 265                 } else {
 266                         xmlnode_insert_data(xmlnode_new_child(query, "name"), "libpurple", -1);
 267                         xmlnode_insert_data(xmlnode_new_child(query, "version"), VERSION, -1);
 268                 }
 269
 270 #if 0
 271                 if(os) {
 272                         xmlnode_insert_data(xmlnode_new_child(query, "os"), os, -1);
 273                         g_free(os);
 274                 }
 275 #endif
 276
 277                 jabber_iq_send(iq);
 278         }
 279 }
 280
 281 void jabber_iq_remove_callback_by_id(JabberStream *js, const char *id)
 282 {
 283         g_hash_table_remove(js->iq_callbacks, id);
 284 }
 285
 286 /**
 287  * Verify that the 'from' attribute of an IQ reply is a valid match for
 288  * a given IQ request. The expected behavior is outlined in section
 289  * 8.1.2.1 of the XMPP CORE spec (RFC 6120). We consider the reply to
 290  * be a valid match if any of the following is true:
 291  * - Request 'to' matches reply 'from' (including the case where
 292  *   neither are set).
 293  * - Request 'to' was my JID (bare or full) and reply 'from' is empty.
 294  * - Request 'to' was empty and reply 'from' is my JID. The spec says
 295  *   we should only allow bare JID, but we also allow full JID for
 296  *   compatibility with some servers.
 297  * - Request 'to' was empty and reply 'from' is server JID. Not allowed by
 298  *   any spec, but for compatibility with some servers.
 299  *
 300  * These rules should allow valid IQ replies while preventing spoofed
 301  * ones.
 302  *
 303  * For more discussion see the "Spoofing of iq ids and misbehaving
 304  * servers" email thread from January 2014 on the jdev and security
 305  * mailing lists. Also see https://developer.pidgin.im/ticket/15879
 306  *
 307  * @return TRUE if this reply is valid for the given request.
 308  */
 309 static gboolean does_reply_from_match_request_to(JabberStream *js, JabberID *to, JabberID *from)
 310 {
 311         if (jabber_id_equal(to, from)) {
 312                 /* Request 'to' matches reply 'from' */
 313                 return TRUE;
 314         }
 315
 316         if (!from && purple_strequal(to->node, js->user->node)
 317                         && purple_strequal(to->domain, js->user->domain)) {
 318                 /* Request 'to' was my JID (bare or full) and reply 'from' is empty */
 319                 return TRUE;
 320         }
 321
 322         if (!to && purple_strequal(from->domain, js->user->domain)) {
 323                 /* Request 'to' is empty and reply 'from' domain matches our domain */
 324
 325                 if (!from->node && !from->resource) {
 326                         /* Reply 'from' is server bare JID */
 327                         return TRUE;
 328                 }
 329
 330                 if (purple_strequal(from->node, js->user->node)
 331                                 && (!from->resource || purple_strequal(from->resource, js->user->resource))) {
 332                         /* Reply 'from' is my full or bare JID */
 333                         return TRUE;
 334                 }
 335         }
 336
 337         return FALSE;
 338 }
 339
 340 void jabber_iq_parse(JabberStream *js, xmlnode *packet)
 341 {
 342         JabberIqCallbackData *jcd;
 343         xmlnode *child, *error, *x;
 344         const char *xmlns;
 345         const char *iq_type, *id, *from;
 346         JabberIqType type = JABBER_IQ_NONE;
 347         gboolean signal_return;
 348         JabberID *from_id;
 349
 350         from = xmlnode_get_attrib(packet, "from");
 351         id = xmlnode_get_attrib(packet, "id");
 352         iq_type = xmlnode_get_attrib(packet, "type");
 353
 354         /*
 355          * Ensure the 'from' attribute is valid. No point in handling a stanza
 356          * of which we don't understand where it came from.
 357          */
 358         from_id = jabber_id_new(from);
 359
 360         if (from && !from_id) {
 361                 purple_debug_error("jabber", "Received an iq with an invalid from: %s\n", from);
 362                 return;
 363         }
 364
 365         /*
 366          * child will be either the first tag child or NULL if there is no child.
 367          * Historically, we used just the 'query' subchild, but newer XEPs use
 368          * differently named children. Grabbing the first child is (for the time
 369          * being) sufficient.
 370          */
 371         for (child = packet->child; child; child = child->next) {
 372                 if (child->type == XMLNODE_TYPE_TAG)
 373                         break;
 374         }
 375
 376         if (iq_type) {
 377                 if (purple_strequal(iq_type, "get"))
 378                         type = JABBER_IQ_GET;
 379                 else if (purple_strequal(iq_type, "set"))
 380                         type = JABBER_IQ_SET;
 381                 else if (purple_strequal(iq_type, "result"))
 382                         type = JABBER_IQ_RESULT;
 383                 else if (purple_strequal(iq_type, "error"))
 384                         type = JABBER_IQ_ERROR;
 385         }
 386
 387         if (type == JABBER_IQ_NONE) {
 388                 purple_debug_error("jabber", "IQ with invalid type ('%s') - ignoring.\n",
 389                                                    iq_type ? iq_type : "(null)");
 390                 jabber_id_free(from_id);
 391                 return;
 392         }
 393
 394         /* All IQs must have an ID, so send an error for a set/get that doesn't */
 395         if(!id || !*id) {
 396
 397                 if(type == JABBER_IQ_SET || type == JABBER_IQ_GET) {
 398                         JabberIq *iq = jabber_iq_new(js, JABBER_IQ_ERROR);
 399
 400                         xmlnode_free(iq->node);
 401                         iq->node = xmlnode_copy(packet);
 402                         if (from) {
 403                                 xmlnode_set_attrib(iq->node, "to", from);
 404                                 xmlnode_remove_attrib(iq->node, "from");
 405                         }
 406
 407                         xmlnode_set_attrib(iq->node, "type", "error");
 408                         /* This id is clearly not useful, but we must put something there for a valid stanza */
 409                         iq->id = jabber_get_next_id(js);
 410                         xmlnode_set_attrib(iq->node, "id", iq->id);
 411                         error = xmlnode_new_child(iq->node, "error");
 412                         xmlnode_set_attrib(error, "type", "modify");
 413                         x = xmlnode_new_child(error, "bad-request");
 414                         xmlnode_set_namespace(x, NS_XMPP_STANZAS);
 415
 416                         jabber_iq_send(iq);
 417                 } else
 418                         purple_debug_error("jabber", "IQ of type '%s' missing id - ignoring.\n",
 419                                            iq_type);
 420
 421                 jabber_id_free(from_id);
 422                 return;
 423         }
 424
 425         signal_return = GPOINTER_TO_INT(purple_signal_emit_return_1(purple_connection_get_prpl(js->gc),
 426                         "jabber-receiving-iq", js->gc, iq_type, id, from, packet));
 427         if (signal_return) {
 428                 jabber_id_free(from_id);
 429                 return;
 430         }
 431
 432         /* First, lets see if a special callback got registered */
 433         if(type == JABBER_IQ_RESULT || type == JABBER_IQ_ERROR) {
 434                 jcd = g_hash_table_lookup(js->iq_callbacks, id);
 435                 if (jcd) {
 436                         if (does_reply_from_match_request_to(js, jcd->to, from_id)) {
 437                                 jcd->callback(js, from, type, id, packet, jcd->data);
 438                                 jabber_iq_remove_callback_by_id(js, id);
 439                                 jabber_id_free(from_id);
 440                                 return;
 441                         } else {
 442                                 char *expected_to;
 443
 444                                 if (jcd->to) {
 445                                         expected_to = jabber_id_get_full_jid(jcd->to);
 446                                 } else {
 447                                         expected_to = jabber_id_get_bare_jid(js->user);
 448                                 }
 449
 450                                 purple_debug_error("jabber", "Got a result iq with id %s from %s instead of expected %s!\n", id, from ? from : "(null)", expected_to);
 451
 452                                 g_free(expected_to);
 453                         }
 454                 }
 455         }
 456
 457         /*
 458          * Apparently not, so let's see if we have a pre-defined handler
 459          * or if an outside plugin is interested.
 460          */
 461         if(child && (xmlns = xmlnode_get_namespace(child))) {
 462                 char *key = g_strdup_printf("%s %s", child->name, xmlns);
 463                 JabberIqHandler *jih = g_hash_table_lookup(iq_handlers, key);
 464                 int signal_ref = GPOINTER_TO_INT(g_hash_table_lookup(signal_iq_handlers, key));
 465                 g_free(key);
 466
 467                 if (signal_ref > 0) {
 468                         signal_return = GPOINTER_TO_INT(purple_signal_emit_return_1(purple_connection_get_prpl(js->gc), "jabber-watched-iq",
 469                                         js->gc, iq_type, id, from, child));
 470                         if (signal_return) {
 471                                 jabber_id_free(from_id);
 472                                 return;
 473                         }
 474                 }
 475
 476                 if(jih) {
 477                         jih(js, from, type, id, child);
 478                         jabber_id_free(from_id);
 479                         return;
 480                 }
 481         }
 482
 483         purple_debug_misc("jabber", "Unhandled IQ with id %s\n", id);
 484
 485         /* If we get here, send the default error reply mandated by XMPP-CORE */
 486         if(type == JABBER_IQ_SET || type == JABBER_IQ_GET) {
 487                 JabberIq *iq = jabber_iq_new(js, JABBER_IQ_ERROR);
 488
 489                 xmlnode_free(iq->node);
 490                 iq->node = xmlnode_copy(packet);
 491                 if (from) {
 492                         xmlnode_set_attrib(iq->node, "to", from);
 493                         xmlnode_remove_attrib(iq->node, "from");
 494                 }
 495
 496                 xmlnode_set_attrib(iq->node, "type", "error");
 497                 error = xmlnode_new_child(iq->node, "error");
 498                 xmlnode_set_attrib(error, "type", "cancel");
 499                 xmlnode_set_attrib(error, "code", "501");
 500                 x = xmlnode_new_child(error, "feature-not-implemented");
 501                 xmlnode_set_namespace(x, NS_XMPP_STANZAS);
 502
 503                 jabber_iq_send(iq);
 504         }
 505
 506         jabber_id_free(from_id);
 507 }
 508
 509 void jabber_iq_register_handler(const char *node, const char *xmlns, JabberIqHandler *handlerfunc)
 510 {
 511         /*
 512          * This is valid because nodes nor namespaces cannot have spaces in them
 513          * (see http://www.w3.org/TR/2006/REC-xml-20060816/ and
 514          * http://www.w3.org/TR/REC-xml-names/)
 515          */
 516         char *key = g_strdup_printf("%s %s", node, xmlns);
 517         g_hash_table_replace(iq_handlers, key, handlerfunc);
 518 }
 519
 520 void jabber_iq_signal_register(const gchar *node, const gchar *xmlns)
 521 {
 522         gchar *key;
 523         int ref;
 524
 525         g_return_if_fail(node != NULL && *node != '\0');
 526         g_return_if_fail(xmlns != NULL && *xmlns != '\0');
 527
 528         key = g_strdup_printf("%s %s", node, xmlns);
 529         ref = GPOINTER_TO_INT(g_hash_table_lookup(signal_iq_handlers, key));
 530         if (ref == 0) {
 531                 g_hash_table_insert(signal_iq_handlers, key, GINT_TO_POINTER(1));
 532         } else {
 533                 g_hash_table_insert(signal_iq_handlers, key, GINT_TO_POINTER(ref + 1));
 534                 g_free(key);
 535         }
 536 }
 537
 538 void jabber_iq_signal_unregister(const gchar *node, const gchar *xmlns)
 539 {
 540         gchar *key;
 541         int ref;
 542
 543         g_return_if_fail(node != NULL && *node != '\0');
 544         g_return_if_fail(xmlns != NULL && *xmlns != '\0');
 545
 546         key = g_strdup_printf("%s %s", node, xmlns);
 547         ref = GPOINTER_TO_INT(g_hash_table_lookup(signal_iq_handlers, key));
 548
 549         if (ref == 1) {
 550                 g_hash_table_remove(signal_iq_handlers, key);
 551         } else if (ref > 1) {
 552                 g_hash_table_insert(signal_iq_handlers, key, GINT_TO_POINTER(ref - 1));
 553         }
 554
 555         g_free(key);
 556 }
 557
 558 void jabber_iq_init(void)
 559 {
 560         iq_handlers = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL);
 561         signal_iq_handlers = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, NULL);
 562
 563         jabber_iq_register_handler("jingle", JINGLE, jingle_parse);
 564         jabber_iq_register_handler("mailbox", NS_GOOGLE_MAIL_NOTIFY,
 565                         jabber_gmail_poke);
 566         jabber_iq_register_handler("new-mail", NS_GOOGLE_MAIL_NOTIFY,
 567                         jabber_gmail_poke);
 568         jabber_iq_register_handler("ping", NS_PING, jabber_ping_parse);
 569         jabber_iq_register_handler("query", NS_GOOGLE_JINGLE_INFO,
 570                         jabber_google_handle_jingle_info);
 571         jabber_iq_register_handler("query", NS_BYTESTREAMS,
 572                         jabber_bytestreams_parse);
 573         jabber_iq_register_handler("query", NS_DISCO_INFO, jabber_disco_info_parse);
 574         jabber_iq_register_handler("query", NS_DISCO_ITEMS, jabber_disco_items_parse);
 575         jabber_iq_register_handler("query", NS_LAST_ACTIVITY, jabber_iq_last_parse);
 576         jabber_iq_register_handler("query", NS_OOB_IQ_DATA, jabber_oob_parse);
 577         jabber_iq_register_handler("query", "jabber:iq:register",
 578                         jabber_register_parse);
 579         jabber_iq_register_handler("query", "jabber:iq:roster",
 580                         jabber_roster_parse);
 581         jabber_iq_register_handler("query", "jabber:iq:version",
 582                         jabber_iq_version_parse);
 583 #ifdef USE_VV
 584         jabber_iq_register_handler("session", NS_GOOGLE_SESSION,
 585                 jabber_google_session_parse);
 586 #endif
 587         jabber_iq_register_handler("block", NS_SIMPLE_BLOCKING, jabber_blocklist_parse_push);
 588         jabber_iq_register_handler("unblock", NS_SIMPLE_BLOCKING, jabber_blocklist_parse_push);
 589         jabber_iq_register_handler("time", NS_ENTITY_TIME, jabber_time_parse);
 590
 591 }
 592
 593 void jabber_iq_uninit(void)
 594 {
 595         g_hash_table_destroy(iq_handlers);
 596         g_hash_table_destroy(signal_iq_handlers);
 597         iq_handlers = signal_iq_handlers = NULL;
 598 }