gio/gnetworkaddress.c

   1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
   2
   3 /* GIO - GLib Input, Output and Streaming Library
   4  *
   5  * Copyright (C) 2008 Red Hat, Inc.
   6  * Copyright (C) 2018 Igalia S.L.
   7  *
   8  * SPDX-License-Identifier: LGPL-2.1-or-later
   9  *
  10  * This library is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU Lesser General Public
  12  * License as published by the Free Software Foundation; either
  13  * version 2.1 of the License, or (at your option) any later version.
  14  *
  15  * This library is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  18  * Lesser General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU Lesser General
  21  * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  22  */
  23
  24 #include "config.h"
  25 #include <glib.h>
  26 #include "glibintl.h"
  27
  28 #include <stdlib.h>
  29 #include "gnetworkaddress.h"
  30 #include "gasyncresult.h"
  31 #include "ginetaddress.h"
  32 #include "ginetsocketaddress.h"
  33 #include "gnetworkingprivate.h"
  34 #include "gproxyaddressenumerator.h"
  35 #include "gresolver.h"
  36 #include "gtask.h"
  37 #include "gsocketaddressenumerator.h"
  38 #include "gioerror.h"
  39 #include "gsocketconnectable.h"
  40
  41 #include <string.h>
  42
  43 /* As recommended by RFC 8305 this is the time it waits for a following
  44    DNS response to come in (ipv4 waiting on ipv6 generally)
  45  */
  46 #define HAPPY_EYEBALLS_RESOLUTION_DELAY_MS 50
  47
  48 /**
  49  * SECTION:gnetworkaddress
  50  * @short_description: A GSocketConnectable for resolving hostnames
  51  * @include: gio/gio.h
  52  *
  53  * #GNetworkAddress provides an easy way to resolve a hostname and
  54  * then attempt to connect to that host, handling the possibility of
  55  * multiple IP addresses and multiple address families.
  56  *
  57  * The enumeration results of resolved addresses *may* be cached as long
  58  * as this object is kept alive which may have unexpected results if
  59  * alive for too long.
  60  *
  61  * See #GSocketConnectable for an example of using the connectable
  62  * interface.
  63  */
  64
  65 /**
  66  * GNetworkAddress:
  67  *
  68  * A #GSocketConnectable for resolving a hostname and connecting to
  69  * that host.
  70  */
  71
  72 struct _GNetworkAddressPrivate {
  73   gchar *hostname;
  74   guint16 port;
  75   GList *cached_sockaddrs;
  76   gchar *scheme;
  77
  78   gint64 resolver_serial;
  79 };
  80
  81 enum {
  82   PROP_0,
  83   PROP_HOSTNAME,
  84   PROP_PORT,
  85   PROP_SCHEME,
  86 };
  87
  88 static void g_network_address_set_property (GObject      *object,
  89                                             guint         prop_id,
  90                                             const GValue *value,
  91                                             GParamSpec   *pspec);
  92 static void g_network_address_get_property (GObject      *object,
  93                                             guint         prop_id,
  94                                             GValue       *value,
  95                                             GParamSpec   *pspec);
  96
  97 static void                      g_network_address_connectable_iface_init       (GSocketConnectableIface *iface);
  98 static GSocketAddressEnumerator *g_network_address_connectable_enumerate        (GSocketConnectable      *connectable);
  99 static GSocketAddressEnumerator *g_network_address_connectable_proxy_enumerate  (GSocketConnectable      *connectable);
 100 static gchar                    *g_network_address_connectable_to_string        (GSocketConnectable      *connectable);
 101
 102 G_DEFINE_TYPE_WITH_CODE (GNetworkAddress, g_network_address, G_TYPE_OBJECT,
 103                          G_ADD_PRIVATE (GNetworkAddress)
 104                          G_IMPLEMENT_INTERFACE (G_TYPE_SOCKET_CONNECTABLE,
 105                                                 g_network_address_connectable_iface_init))
 106
 107 static void
 108 g_network_address_finalize (GObject *object)
 109 {
 110   GNetworkAddress *addr = G_NETWORK_ADDRESS (object);
 111
 112   g_free (addr->priv->hostname);
 113   g_free (addr->priv->scheme);
 114   g_list_free_full (addr->priv->cached_sockaddrs, g_object_unref);
 115
 116   G_OBJECT_CLASS (g_network_address_parent_class)->finalize (object);
 117 }
 118
 119 static void
 120 g_network_address_class_init (GNetworkAddressClass *klass)
 121 {
 122   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 123
 124   gobject_class->set_property = g_network_address_set_property;
 125   gobject_class->get_property = g_network_address_get_property;
 126   gobject_class->finalize = g_network_address_finalize;
 127
 128   g_object_class_install_property (gobject_class, PROP_HOSTNAME,
 129                                    g_param_spec_string ("hostname",
 130                                                         P_("Hostname"),
 131                                                         P_("Hostname to resolve"),
 132                                                         NULL,
 133                                                         G_PARAM_READWRITE |
 134                                                         G_PARAM_CONSTRUCT_ONLY |
 135                                                         G_PARAM_STATIC_STRINGS));
 136   g_object_class_install_property (gobject_class, PROP_PORT,
 137                                    g_param_spec_uint ("port",
 138                                                       P_("Port"),
 139                                                       P_("Network port"),
 140                                                       0, 65535, 0,
 141                                                       G_PARAM_READWRITE |
 142                                                       G_PARAM_CONSTRUCT_ONLY |
 143                                                       G_PARAM_STATIC_STRINGS));
 144
 145   g_object_class_install_property (gobject_class, PROP_SCHEME,
 146                                    g_param_spec_string ("scheme",
 147                                                         P_("Scheme"),
 148                                                         P_("URI Scheme"),
 149                                                         NULL,
 150                                                         G_PARAM_READWRITE |
 151                                                         G_PARAM_CONSTRUCT_ONLY |
 152                                                         G_PARAM_STATIC_STRINGS));
 153 }
 154
 155 static void
 156 g_network_address_connectable_iface_init (GSocketConnectableIface *connectable_iface)
 157 {
 158   connectable_iface->enumerate  = g_network_address_connectable_enumerate;
 159   connectable_iface->proxy_enumerate = g_network_address_connectable_proxy_enumerate;
 160   connectable_iface->to_string = g_network_address_connectable_to_string;
 161 }
 162
 163 static void
 164 g_network_address_init (GNetworkAddress *addr)
 165 {
 166   addr->priv = g_network_address_get_instance_private (addr);
 167 }
 168
 169 static void
 170 g_network_address_set_property (GObject      *object,
 171                                 guint         prop_id,
 172                                 const GValue *value,
 173                                 GParamSpec   *pspec)
 174 {
 175   GNetworkAddress *addr = G_NETWORK_ADDRESS (object);
 176
 177   switch (prop_id)
 178     {
 179     case PROP_HOSTNAME:
 180       g_free (addr->priv->hostname);
 181       addr->priv->hostname = g_value_dup_string (value);
 182       break;
 183
 184     case PROP_PORT:
 185       addr->priv->port = g_value_get_uint (value);
 186       break;
 187
 188     case PROP_SCHEME:
 189       g_free (addr->priv->scheme);
 190       addr->priv->scheme = g_value_dup_string (value);
 191       break;
 192
 193     default:
 194       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 195       break;
 196     }
 197
 198 }
 199
 200 static void
 201 g_network_address_get_property (GObject    *object,
 202                                 guint       prop_id,
 203                                 GValue     *value,
 204                                 GParamSpec *pspec)
 205 {
 206   GNetworkAddress *addr = G_NETWORK_ADDRESS (object);
 207
 208   switch (prop_id)
 209     {
 210     case PROP_HOSTNAME:
 211       g_value_set_string (value, addr->priv->hostname);
 212       break;
 213
 214     case PROP_PORT:
 215       g_value_set_uint (value, addr->priv->port);
 216       break;
 217
 218     case PROP_SCHEME:
 219       g_value_set_string (value, addr->priv->scheme);
 220       break;
 221
 222     default:
 223       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 224       break;
 225     }
 226
 227 }
 228
 229 /*
 230  * inet_addresses_to_inet_socket_addresses:
 231  * @addresses: (transfer full): #GList of #GInetAddress
 232  *
 233  * Returns: (transfer full): #GList of #GInetSocketAddress
 234  */
 235 static GList *
 236 inet_addresses_to_inet_socket_addresses (GNetworkAddress *addr,
 237                                          GList           *addresses)
 238 {
 239   GList *a, *socket_addresses = NULL;
 240
 241   for (a = addresses; a; a = a->next)
 242     {
 243       GSocketAddress *sockaddr = g_inet_socket_address_new (a->data, addr->priv->port);
 244       socket_addresses = g_list_append (socket_addresses, g_steal_pointer (&sockaddr));
 245       g_object_unref (a->data);
 246     }
 247
 248   g_list_free (addresses);
 249   return socket_addresses;
 250 }
 251
 252 /*
 253  * g_network_address_set_cached_addresses:
 254  * @addr: A #GNetworkAddress
 255  * @addresses: (transfer full): List of #GInetAddress or #GInetSocketAddress
 256  * @resolver_serial: Serial of #GResolver used
 257  *
 258  * Consumes @addresses and uses them to replace the current internal list.
 259  */
 260 static void
 261 g_network_address_set_cached_addresses (GNetworkAddress *addr,
 262                                         GList           *addresses,
 263                                         guint64          resolver_serial)
 264 {
 265   g_assert (addresses != NULL);
 266
 267   if (addr->priv->cached_sockaddrs)
 268     g_list_free_full (addr->priv->cached_sockaddrs, g_object_unref);
 269
 270   if (G_IS_INET_SOCKET_ADDRESS (addresses->data))
 271     addr->priv->cached_sockaddrs = g_steal_pointer (&addresses);
 272   else
 273     addr->priv->cached_sockaddrs = inet_addresses_to_inet_socket_addresses (addr, g_steal_pointer (&addresses));
 274   addr->priv->resolver_serial = resolver_serial;
 275 }
 276
 277 static gboolean
 278 g_network_address_parse_sockaddr (GNetworkAddress *addr)
 279 {
 280   GSocketAddress *sockaddr;
 281
 282   g_assert (addr->priv->cached_sockaddrs == NULL);
 283
 284   sockaddr = g_inet_socket_address_new_from_string (addr->priv->hostname,
 285                                                     addr->priv->port);
 286   if (sockaddr)
 287     {
 288       addr->priv->cached_sockaddrs = g_list_append (addr->priv->cached_sockaddrs, sockaddr);
 289       return TRUE;
 290     }
 291   else
 292     return FALSE;
 293 }
 294
 295 /**
 296  * g_network_address_new:
 297  * @hostname: the hostname
 298  * @port: the port
 299  *
 300  * Creates a new #GSocketConnectable for connecting to the given
 301  * @hostname and @port.
 302  *
 303  * Note that depending on the configuration of the machine, a
 304  * @hostname of `localhost` may refer to the IPv4 loopback address
 305  * only, or to both IPv4 and IPv6; use
 306  * g_network_address_new_loopback() to create a #GNetworkAddress that
 307  * is guaranteed to resolve to both addresses.
 308  *
 309  * Returns: (transfer full) (type GNetworkAddress): the new #GNetworkAddress
 310  *
 311  * Since: 2.22
 312  */
 313 GSocketConnectable *
 314 g_network_address_new (const gchar *hostname,
 315                        guint16      port)
 316 {
 317   return g_object_new (G_TYPE_NETWORK_ADDRESS,
 318                        "hostname", hostname,
 319                        "port", port,
 320                        NULL);
 321 }
 322
 323 /**
 324  * g_network_address_new_loopback:
 325  * @port: the port
 326  *
 327  * Creates a new #GSocketConnectable for connecting to the local host
 328  * over a loopback connection to the given @port. This is intended for
 329  * use in connecting to local services which may be running on IPv4 or
 330  * IPv6.
 331  *
 332  * The connectable will return IPv4 and IPv6 loopback addresses,
 333  * regardless of how the host resolves `localhost`. By contrast,
 334  * g_network_address_new() will often only return an IPv4 address when
 335  * resolving `localhost`, and an IPv6 address for `localhost6`.
 336  *
 337  * g_network_address_get_hostname() will always return `localhost` for
 338  * a #GNetworkAddress created with this constructor.
 339  *
 340  * Returns: (transfer full) (type GNetworkAddress): the new #GNetworkAddress
 341  *
 342  * Since: 2.44
 343  */
 344 GSocketConnectable *
 345 g_network_address_new_loopback (guint16 port)
 346 {
 347   GNetworkAddress *addr;
 348   GList *addrs = NULL;
 349
 350   addr = g_object_new (G_TYPE_NETWORK_ADDRESS,
 351                        "hostname", "localhost",
 352                        "port", port,
 353                        NULL);
 354
 355   addrs = g_list_append (addrs, g_inet_address_new_loopback (AF_INET6));
 356   addrs = g_list_append (addrs, g_inet_address_new_loopback (AF_INET));
 357   g_network_address_set_cached_addresses (addr, g_steal_pointer (&addrs), 0);
 358
 359   return G_SOCKET_CONNECTABLE (addr);
 360 }
 361
 362 /**
 363  * g_network_address_parse:
 364  * @host_and_port: the hostname and optionally a port
 365  * @default_port: the default port if not in @host_and_port
 366  * @error: a pointer to a #GError, or %NULL
 367  *
 368  * Creates a new #GSocketConnectable for connecting to the given
 369  * @hostname and @port. May fail and return %NULL in case
 370  * parsing @host_and_port fails.
 371  *
 372  * @host_and_port may be in any of a number of recognised formats; an IPv6
 373  * address, an IPv4 address, or a domain name (in which case a DNS
 374  * lookup is performed). Quoting with [] is supported for all address
 375  * types. A port override may be specified in the usual way with a
 376  * colon.
 377  *
 378  * If no port is specified in @host_and_port then @default_port will be
 379  * used as the port number to connect to.
 380  *
 381  * In general, @host_and_port is expected to be provided by the user
 382  * (allowing them to give the hostname, and a port override if necessary)
 383  * and @default_port is expected to be provided by the application.
 384  *
 385  * (The port component of @host_and_port can also be specified as a
 386  * service name rather than as a numeric port, but this functionality
 387  * is deprecated, because it depends on the contents of /etc/services,
 388  * which is generally quite sparse on platforms other than Linux.)
 389  *
 390  * Returns: (transfer full) (type GNetworkAddress): the new
 391  *   #GNetworkAddress, or %NULL on error
 392  *
 393  * Since: 2.22
 394  */
 395 GSocketConnectable *
 396 g_network_address_parse (const gchar  *host_and_port,
 397                          guint16       default_port,
 398                          GError      **error)
 399 {
 400   GSocketConnectable *connectable;
 401   const gchar *port;
 402   guint16 portnum;
 403   gchar *name;
 404
 405   g_return_val_if_fail (host_and_port != NULL, NULL);
 406
 407   port = NULL;
 408   if (host_and_port[0] == '[')
 409     /* escaped host part (to allow, eg. "[2001:db8::1]:888") */
 410     {
 411       const gchar *end;
 412
 413       end = strchr (host_and_port, ']');
 414       if (end == NULL)
 415         {
 416           g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 417                        _("Hostname “%s” contains “[” but not “]”"), host_and_port);
 418           return NULL;
 419         }
 420
 421       if (end[1] == '\0')
 422         port = NULL;
 423       else if (end[1] == ':')
 424         port = &end[2];
 425       else
 426         {
 427           g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 428                        "The ']' character (in hostname '%s') must come at the"
 429                        " end or be immediately followed by ':' and a port",
 430                        host_and_port);
 431           return NULL;
 432         }
 433
 434       name = g_strndup (host_and_port + 1, end - host_and_port - 1);
 435     }
 436
 437   else if ((port = strchr (host_and_port, ':')))
 438     /* string has a ':' in it */
 439     {
 440       /* skip ':' */
 441       port++;
 442
 443       if (strchr (port, ':'))
 444         /* more than one ':' in string */
 445         {
 446           /* this is actually an unescaped IPv6 address */
 447           name = g_strdup (host_and_port);
 448           port = NULL;
 449         }
 450       else
 451         name = g_strndup (host_and_port, port - host_and_port - 1);
 452     }
 453
 454   else
 455     /* plain hostname, no port */
 456     name = g_strdup (host_and_port);
 457
 458   if (port != NULL)
 459     {
 460       if (port[0] == '\0')
 461         {
 462           g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 463                        "If a ':' character is given, it must be followed by a "
 464                        "port (in hostname '%s').", host_and_port);
 465           g_free (name);
 466           return NULL;
 467         }
 468
 469       else if ('0' <= port[0] && port[0] <= '9')
 470         {
 471           char *end;
 472           long value;
 473
 474           value = strtol (port, &end, 10);
 475           if (*end != '\0' || value < 0 || value > G_MAXUINT16)
 476             {
 477               g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 478                            "Invalid numeric port '%s' specified in hostname '%s'",
 479                            port, host_and_port);
 480               g_free (name);
 481               return NULL;
 482             }
 483
 484           portnum = value;
 485         }
 486
 487       else
 488         {
 489           if (!g_getservbyname_ntohs (port, "tcp", &portnum))
 490             {
 491               g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 492                            "Unknown service '%s' specified in hostname '%s'",
 493                            port, host_and_port);
 494 #ifdef HAVE_ENDSERVENT
 495               endservent ();
 496 #endif
 497               g_free (name);
 498               return NULL;
 499             }
 500
 501 #ifdef HAVE_ENDSERVENT
 502           endservent ();
 503 #endif
 504         }
 505     }
 506   else
 507     {
 508       /* No port in host_and_port */
 509       portnum = default_port;
 510     }
 511
 512   connectable = g_network_address_new (name, portnum);
 513   g_free (name);
 514
 515   return connectable;
 516 }
 517
 518 /**
 519  * g_network_address_parse_uri:
 520  * @uri: the hostname and optionally a port
 521  * @default_port: The default port if none is found in the URI
 522  * @error: a pointer to a #GError, or %NULL
 523  *
 524  * Creates a new #GSocketConnectable for connecting to the given
 525  * @uri. May fail and return %NULL in case parsing @uri fails.
 526  *
 527  * Using this rather than g_network_address_new() or
 528  * g_network_address_parse() allows #GSocketClient to determine
 529  * when to use application-specific proxy protocols.
 530  *
 531  * Returns: (transfer full) (type GNetworkAddress): the new
 532  *   #GNetworkAddress, or %NULL on error
 533  *
 534  * Since: 2.26
 535  */
 536 GSocketConnectable *
 537 g_network_address_parse_uri (const gchar  *uri,
 538                              guint16       default_port,
 539                              GError      **error)
 540 {
 541   GSocketConnectable *conn = NULL;
 542   gchar *scheme = NULL;
 543   gchar *hostname = NULL;
 544   gint port;
 545
 546   if (!g_uri_split_network (uri, G_URI_FLAGS_NONE,
 547                             &scheme, &hostname, &port, NULL))
 548     {
 549       g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
 550                    "Invalid URI ‘%s’", uri);
 551       return NULL;
 552     }
 553
 554   if (port <= 0)
 555     port = default_port;
 556
 557   conn = g_object_new (G_TYPE_NETWORK_ADDRESS,
 558                        "hostname", hostname,
 559                        "port", (guint) port,
 560                        "scheme", scheme,
 561                        NULL);
 562   g_free (scheme);
 563   g_free (hostname);
 564
 565   return conn;
 566 }
 567
 568 /**
 569  * g_network_address_get_hostname:
 570  * @addr: a #GNetworkAddress
 571  *
 572  * Gets @addr's hostname. This might be either UTF-8 or ASCII-encoded,
 573  * depending on what @addr was created with.
 574  *
 575  * Returns: @addr's hostname
 576  *
 577  * Since: 2.22
 578  */
 579 const gchar *
 580 g_network_address_get_hostname (GNetworkAddress *addr)
 581 {
 582   g_return_val_if_fail (G_IS_NETWORK_ADDRESS (addr), NULL);
 583
 584   return addr->priv->hostname;
 585 }
 586
 587 /**
 588  * g_network_address_get_port:
 589  * @addr: a #GNetworkAddress
 590  *
 591  * Gets @addr's port number
 592  *
 593  * Returns: @addr's port (which may be 0)
 594  *
 595  * Since: 2.22
 596  */
 597 guint16
 598 g_network_address_get_port (GNetworkAddress *addr)
 599 {
 600   g_return_val_if_fail (G_IS_NETWORK_ADDRESS (addr), 0);
 601
 602   return addr->priv->port;
 603 }
 604
 605 /**
 606  * g_network_address_get_scheme:
 607  * @addr: a #GNetworkAddress
 608  *
 609  * Gets @addr's scheme
 610  *
 611  * Returns: (nullable): @addr's scheme (%NULL if not built from URI)
 612  *
 613  * Since: 2.26
 614  */
 615 const gchar *
 616 g_network_address_get_scheme (GNetworkAddress *addr)
 617 {
 618   g_return_val_if_fail (G_IS_NETWORK_ADDRESS (addr), NULL);
 619
 620   return addr->priv->scheme;
 621 }
 622
 623 #define G_TYPE_NETWORK_ADDRESS_ADDRESS_ENUMERATOR (_g_network_address_address_enumerator_get_type ())
 624 #define G_NETWORK_ADDRESS_ADDRESS_ENUMERATOR(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), G_TYPE_NETWORK_ADDRESS_ADDRESS_ENUMERATOR, GNetworkAddressAddressEnumerator))
 625
 626 typedef enum {
 627   RESOLVE_STATE_NONE = 0,
 628   RESOLVE_STATE_WAITING_ON_IPV4 = 1 << 0,
 629   RESOLVE_STATE_WAITING_ON_IPV6 = 1 << 1,
 630 } ResolveState;
 631
 632 typedef struct {
 633   GSocketAddressEnumerator parent_instance;
 634
 635   GNetworkAddress *addr; /* (owned) */
 636   GList *addresses; /* (owned) (nullable) */
 637   GList *current_item; /* (unowned) (nullable) */
 638   GTask *queued_task; /* (owned) (nullable) */
 639   GTask *waiting_task; /* (owned) (nullable) */
 640   GError *last_error; /* (owned) (nullable) */
 641   GSource *wait_source; /* (owned) (nullable) */
 642   GMainContext *context; /* (owned) (nullable) */
 643   ResolveState state;
 644 } GNetworkAddressAddressEnumerator;
 645
 646 typedef struct {
 647   GSocketAddressEnumeratorClass parent_class;
 648
 649 } GNetworkAddressAddressEnumeratorClass;
 650
 651 static GType _g_network_address_address_enumerator_get_type (void);
 652 G_DEFINE_TYPE (GNetworkAddressAddressEnumerator, _g_network_address_address_enumerator, G_TYPE_SOCKET_ADDRESS_ENUMERATOR)
 653
 654 static void
 655 g_network_address_address_enumerator_finalize (GObject *object)
 656 {
 657   GNetworkAddressAddressEnumerator *addr_enum =
 658     G_NETWORK_ADDRESS_ADDRESS_ENUMERATOR (object);
 659
 660   if (addr_enum->wait_source)
 661     {
 662       g_source_destroy (addr_enum->wait_source);
 663       g_clear_pointer (&addr_enum->wait_source, g_source_unref);
 664     }
 665   g_clear_object (&addr_enum->queued_task);
 666   g_clear_object (&addr_enum->waiting_task);
 667   g_clear_error (&addr_enum->last_error);
 668   g_object_unref (addr_enum->addr);
 669   g_clear_pointer (&addr_enum->context, g_main_context_unref);
 670   g_list_free_full (addr_enum->addresses, g_object_unref);
 671
 672   G_OBJECT_CLASS (_g_network_address_address_enumerator_parent_class)->finalize (object);
 673 }
 674
 675 static inline GSocketFamily
 676 get_address_family (GInetSocketAddress *address)
 677 {
 678   return g_inet_address_get_family (g_inet_socket_address_get_address (address));
 679 }
 680
 681 static void
 682 list_split_families (GList  *list,
 683                      GList **out_ipv4,
 684                      GList **out_ipv6)
 685 {
 686   g_assert (out_ipv4);
 687   g_assert (out_ipv6);
 688
 689   while (list)
 690     {
 691       GSocketFamily family = get_address_family (list->data);
 692       switch (family)
 693         {
 694           case G_SOCKET_FAMILY_IPV4:
 695             *out_ipv4 = g_list_prepend (*out_ipv4, list->data);
 696             break;
 697           case G_SOCKET_FAMILY_IPV6:
 698             *out_ipv6 = g_list_prepend (*out_ipv6, list->data);
 699             break;
 700           case G_SOCKET_FAMILY_INVALID:
 701           case G_SOCKET_FAMILY_UNIX:
 702             g_assert_not_reached ();
 703         }
 704
 705       list = g_list_next (list);
 706     }
 707
 708   *out_ipv4 = g_list_reverse (*out_ipv4);
 709   *out_ipv6 = g_list_reverse (*out_ipv6);
 710 }
 711
 712 static GList *
 713 list_interleave_families (GList *list1,
 714                           GList *list2)
 715 {
 716   GList *interleaved = NULL;
 717
 718   while (list1 || list2)
 719     {
 720       if (list1)
 721         {
 722           interleaved = g_list_append (interleaved, list1->data);
 723           list1 = g_list_delete_link (list1, list1);
 724         }
 725       if (list2)
 726         {
 727           interleaved = g_list_append (interleaved, list2->data);
 728           list2 = g_list_delete_link (list2, list2);
 729         }
 730     }
 731
 732   return interleaved;
 733 }
 734
 735 /* list_copy_interleaved:
 736  * @list: (transfer container): List to copy
 737  *
 738  * Does a shallow copy of a list with address families interleaved.
 739  *
 740  * For example:
 741  *   Input: [ipv6, ipv6, ipv4, ipv4]
 742  *   Output: [ipv6, ipv4, ipv6, ipv4]
 743  *
 744  * Returns: (transfer container): A new list
 745  */
 746 static GList *
 747 list_copy_interleaved (GList *list)
 748 {
 749   GList *ipv4 = NULL, *ipv6 = NULL;
 750
 751   list_split_families (list, &ipv4, &ipv6);
 752   return list_interleave_families (ipv6, ipv4);
 753 }
 754
 755 /* list_concat_interleaved:
 756  * @parent_list: (transfer container): Already existing list
 757  * @current_item: (transfer container): Item after which to resort
 758  * @new_list: (transfer container): New list to be interleaved and concatenated
 759  *
 760  * This differs from g_list_concat() + list_copy_interleaved() in that it sorts
 761  * items in the previous list starting from @current_item and concats the results
 762  * to @parent_list.
 763  *
 764  * Returns: (transfer container): New start of list
 765  */
 766 static GList *
 767 list_concat_interleaved (GList *parent_list,
 768                          GList *current_item,
 769                          GList *new_list)
 770 {
 771   GList *ipv4 = NULL, *ipv6 = NULL, *interleaved, *trailing = NULL;
 772   GSocketFamily last_family = G_SOCKET_FAMILY_IPV4; /* Default to starting with ipv6 */
 773
 774   if (current_item)
 775     {
 776       last_family = get_address_family (current_item->data);
 777
 778       /* Unused addresses will get removed, resorted, then readded */
 779       trailing = g_list_next (current_item);
 780       current_item->next = NULL;
 781     }
 782
 783   list_split_families (trailing, &ipv4, &ipv6);
 784   list_split_families (new_list, &ipv4, &ipv6);
 785   g_list_free (new_list);
 786
 787   if (trailing)
 788     g_list_free (trailing);
 789
 790   if (last_family == G_SOCKET_FAMILY_IPV4)
 791     interleaved = list_interleave_families (ipv6, ipv4);
 792   else
 793     interleaved = list_interleave_families (ipv4, ipv6);
 794
 795   return g_list_concat (parent_list, interleaved);
 796 }
 797
 798 static void
 799 maybe_update_address_cache (GNetworkAddressAddressEnumerator *addr_enum,
 800                             GResolver                        *resolver)
 801 {
 802   GList *addresses, *p;
 803
 804   /* Only cache complete results */
 805   if (addr_enum->state & RESOLVE_STATE_WAITING_ON_IPV4 || addr_enum->state & RESOLVE_STATE_WAITING_ON_IPV6)
 806     return;
 807
 808   /* The enumerators list will not necessarily be fully sorted */
 809   addresses = list_copy_interleaved (addr_enum->addresses);
 810   for (p = addresses; p; p = p->next)
 811     g_object_ref (p->data);
 812
 813   g_network_address_set_cached_addresses (addr_enum->addr, g_steal_pointer (&addresses), g_resolver_get_serial (resolver));
 814 }
 815
 816 static void
 817 g_network_address_address_enumerator_add_addresses (GNetworkAddressAddressEnumerator *addr_enum,
 818                                                     GList                            *addresses,
 819                                                     GResolver                        *resolver)
 820 {
 821   GList *new_addresses = inet_addresses_to_inet_socket_addresses (addr_enum->addr, addresses);
 822
 823   if (addr_enum->addresses == NULL)
 824     addr_enum->addresses = g_steal_pointer (&new_addresses);
 825   else
 826     addr_enum->addresses = list_concat_interleaved (addr_enum->addresses, addr_enum->current_item, g_steal_pointer (&new_addresses));
 827
 828   maybe_update_address_cache (addr_enum, resolver);
 829 }
 830
 831 static gpointer
 832 copy_object (gconstpointer src,
 833              gpointer      user_data)
 834 {
 835   return g_object_ref (G_OBJECT (src));
 836 }
 837
 838 static GSocketAddress *
 839 init_and_query_next_address (GNetworkAddressAddressEnumerator *addr_enum)
 840 {
 841   GList *next_item;
 842
 843   if (addr_enum->addresses == NULL)
 844     addr_enum->addresses = g_list_copy_deep (addr_enum->addr->priv->cached_sockaddrs,
 845                                              copy_object, NULL);
 846
 847   /* We always want to look at the next item at call time to get the latest results.
 848      That means that sometimes ->next is NULL this call but is valid next call.
 849    */
 850   if (addr_enum->current_item == NULL)
 851     next_item = addr_enum->current_item = addr_enum->addresses;
 852   else
 853     next_item = g_list_next (addr_enum->current_item);
 854
 855   if (next_item)
 856     {
 857       addr_enum->current_item = next_item;
 858       return g_object_ref (addr_enum->current_item->data);
 859     }
 860   else
 861     return NULL;
 862 }
 863
 864 static GSocketAddress *
 865 g_network_address_address_enumerator_next (GSocketAddressEnumerator  *enumerator,
 866                                            GCancellable              *cancellable,
 867                                            GError                   **error)
 868 {
 869   GNetworkAddressAddressEnumerator *addr_enum =
 870     G_NETWORK_ADDRESS_ADDRESS_ENUMERATOR (enumerator);
 871
 872   if (addr_enum->addresses == NULL)
 873     {
 874       GNetworkAddress *addr = addr_enum->addr;
 875       GResolver *resolver = g_resolver_get_default ();
 876       gint64 serial = g_resolver_get_serial (resolver);
 877
 878       if (addr->priv->resolver_serial != 0 &&
 879           addr->priv->resolver_serial != serial)
 880         {
 881           /* Resolver has reloaded, discard cached addresses */
 882           g_list_free_full (addr->priv->cached_sockaddrs, g_object_unref);
 883           addr->priv->cached_sockaddrs = NULL;
 884         }
 885
 886       if (!addr->priv->cached_sockaddrs)
 887         g_network_address_parse_sockaddr (addr);
 888       if (!addr->priv->cached_sockaddrs)
 889         {
 890           GList *addresses;
 891
 892           addresses = g_resolver_lookup_by_name (resolver,
 893                                                  addr->priv->hostname,
 894                                                  cancellable, error);
 895           if (!addresses)
 896             {
 897               g_object_unref (resolver);
 898               return NULL;
 899             }
 900
 901           g_network_address_set_cached_addresses (addr, g_steal_pointer (&addresses), serial);
 902         }
 903
 904       g_object_unref (resolver);
 905     }
 906
 907   return init_and_query_next_address (addr_enum);
 908 }
 909
 910 static void
 911 complete_queued_task (GNetworkAddressAddressEnumerator *addr_enum,
 912                       GTask                            *task,
 913                       GError                           *error)
 914 {
 915   if (error)
 916     g_task_return_error (task, error);
 917   else
 918     {
 919       GSocketAddress *sockaddr = init_and_query_next_address (addr_enum);
 920       g_task_return_pointer (task, g_steal_pointer (&sockaddr), g_object_unref);
 921     }
 922   g_object_unref (task);
 923 }
 924
 925 static int
 926 on_address_timeout (gpointer user_data)
 927 {
 928   GNetworkAddressAddressEnumerator *addr_enum = user_data;
 929
 930   /* Upon completion it may get unref'd by the owner */
 931   g_object_ref (addr_enum);
 932
 933   if (addr_enum->queued_task != NULL)
 934       complete_queued_task (addr_enum, g_steal_pointer (&addr_enum->queued_task),
 935                             g_steal_pointer (&addr_enum->last_error));
 936   else if (addr_enum->waiting_task != NULL)
 937       complete_queued_task (addr_enum, g_steal_pointer (&addr_enum->waiting_task),
 938                             NULL);
 939
 940   g_clear_pointer (&addr_enum->wait_source, g_source_unref);
 941   g_object_unref (addr_enum);
 942
 943   return G_SOURCE_REMOVE;
 944 }
 945
 946 static void
 947 got_ipv6_addresses (GObject      *source_object,
 948                     GAsyncResult *result,
 949                     gpointer      user_data)
 950 {
 951   GNetworkAddressAddressEnumerator *addr_enum = user_data;
 952   GResolver *resolver = G_RESOLVER (source_object);
 953   GList *addresses;
 954   GError *error = NULL;
 955
 956   addr_enum->state ^= RESOLVE_STATE_WAITING_ON_IPV6;
 957
 958   addresses = g_resolver_lookup_by_name_with_flags_finish (resolver, result, &error);
 959   if (!error)
 960     g_network_address_address_enumerator_add_addresses (addr_enum, g_steal_pointer (&addresses), resolver);
 961   else
 962     g_debug ("IPv6 DNS error: %s", error->message);
 963
 964   /* If ipv4 was first and waiting on us it can stop waiting */
 965   if (addr_enum->wait_source)
 966     {
 967       g_source_destroy (addr_enum->wait_source);
 968       g_clear_pointer (&addr_enum->wait_source, g_source_unref);
 969     }
 970
 971   /* If we got an error before ipv4 then let its response handle it.
 972    * If we get ipv6 response first or error second then
 973    * immediately complete the task.
 974    */
 975   if (error != NULL && !addr_enum->last_error && (addr_enum->state & RESOLVE_STATE_WAITING_ON_IPV4))
 976     {
 977       /* ipv6 lookup failed, but ipv4 is still outstanding.  wait. */
 978       addr_enum->last_error = g_steal_pointer (&error);
 979     }
 980   else if (addr_enum->waiting_task != NULL)
 981     {
 982       complete_queued_task (addr_enum, g_steal_pointer (&addr_enum->waiting_task), NULL);
 983     }
 984   else if (addr_enum->queued_task != NULL)
 985     {
 986       GError *task_error = NULL;
 987
 988       /* If both errored just use the ipv6 one,
 989          but if ipv6 errored and ipv4 didn't we don't error */
 990       if (error != NULL && addr_enum->last_error)
 991           task_error = g_steal_pointer (&error);
 992
 993       g_clear_error (&addr_enum->last_error);
 994       complete_queued_task (addr_enum, g_steal_pointer (&addr_enum->queued_task),
 995                             g_steal_pointer (&task_error));
 996     }
 997
 998   g_clear_error (&error);
 999   g_object_unref (addr_enum);
1000 }
1001
1002 static void
1003 got_ipv4_addresses (GObject      *source_object,
1004                     GAsyncResult *result,
1005                     gpointer      user_data)
1006 {
1007   GNetworkAddressAddressEnumerator *addr_enum = user_data;
1008   GResolver *resolver = G_RESOLVER (source_object);
1009   GList *addresses;
1010   GError *error = NULL;
1011
1012   addr_enum->state ^= RESOLVE_STATE_WAITING_ON_IPV4;
1013
1014   addresses = g_resolver_lookup_by_name_with_flags_finish (resolver, result, &error);
1015   if (!error)
1016     g_network_address_address_enumerator_add_addresses (addr_enum, g_steal_pointer (&addresses), resolver);
1017   else
1018     g_debug ("IPv4 DNS error: %s", error->message);
1019
1020   if (addr_enum->wait_source)
1021     {
1022       g_source_destroy (addr_enum->wait_source);
1023       g_clear_pointer (&addr_enum->wait_source, g_source_unref);
1024     }
1025
1026   /* If ipv6 already came in and errored then we return.
1027    * If ipv6 returned successfully then we don't need to do anything unless
1028    * another enumeration was waiting on us.
1029    * If ipv6 hasn't come we should wait a short while for it as RFC 8305 suggests.
1030    */
1031   if (addr_enum->last_error)
1032     {
1033       g_assert (addr_enum->queued_task);
1034       g_clear_error (&addr_enum->last_error);
1035       complete_queued_task (addr_enum, g_steal_pointer (&addr_enum->queued_task),
1036                             g_steal_pointer (&error));
1037     }
1038   else if (addr_enum->waiting_task != NULL)
1039     {
1040       complete_queued_task (addr_enum, g_steal_pointer (&addr_enum->waiting_task), NULL);
1041     }
1042   else if (addr_enum->queued_task != NULL)
1043     {
1044       addr_enum->last_error = g_steal_pointer (&error);
1045       addr_enum->wait_source = g_timeout_source_new (HAPPY_EYEBALLS_RESOLUTION_DELAY_MS);
1046       g_source_set_callback (addr_enum->wait_source,
1047                              on_address_timeout,
1048                              addr_enum, NULL);
1049       g_source_attach (addr_enum->wait_source, addr_enum->context);
1050     }
1051
1052   g_clear_error (&error);
1053   g_object_unref (addr_enum);
1054 }
1055
1056 static void
1057 g_network_address_address_enumerator_next_async (GSocketAddressEnumerator  *enumerator,
1058                                                  GCancellable              *cancellable,
1059                                                  GAsyncReadyCallback        callback,
1060                                                  gpointer                   user_data)
1061 {
1062   GNetworkAddressAddressEnumerator *addr_enum =
1063     G_NETWORK_ADDRESS_ADDRESS_ENUMERATOR (enumerator);
1064   GSocketAddress *sockaddr;
1065   GTask *task;
1066
1067   task = g_task_new (addr_enum, cancellable, callback, user_data);
1068   g_task_set_source_tag (task, g_network_address_address_enumerator_next_async);
1069
1070   if (addr_enum->addresses == NULL && addr_enum->state == RESOLVE_STATE_NONE)
1071     {
1072       GNetworkAddress *addr = addr_enum->addr;
1073       GResolver *resolver = g_resolver_get_default ();
1074       gint64 serial = g_resolver_get_serial (resolver);
1075
1076       if (addr->priv->resolver_serial != 0 &&
1077           addr->priv->resolver_serial != serial)
1078         {
1079           /* Resolver has reloaded, discard cached addresses */
1080           g_list_free_full (addr->priv->cached_sockaddrs, g_object_unref);
1081           addr->priv->cached_sockaddrs = NULL;
1082         }
1083
1084       if (addr->priv->cached_sockaddrs == NULL)
1085         {
1086           if (g_network_address_parse_sockaddr (addr))
1087             complete_queued_task (addr_enum, task, NULL);
1088           else
1089             {
1090               /* It does not make sense for this to be called multiple
1091                * times before the initial callback has been called */
1092               g_assert (addr_enum->queued_task == NULL);
1093
1094               addr_enum->state = RESOLVE_STATE_WAITING_ON_IPV4 | RESOLVE_STATE_WAITING_ON_IPV6;
1095               addr_enum->queued_task = g_steal_pointer (&task);
1096               /* Look up in parallel as per RFC 8305 */
1097               g_resolver_lookup_by_name_with_flags_async (resolver,
1098                                                           addr->priv->hostname,
1099                                                           G_RESOLVER_NAME_LOOKUP_FLAGS_IPV6_ONLY,
1100                                                           cancellable,
1101                                                           got_ipv6_addresses, g_object_ref (addr_enum));
1102               g_resolver_lookup_by_name_with_flags_async (resolver,
1103                                                           addr->priv->hostname,
1104                                                           G_RESOLVER_NAME_LOOKUP_FLAGS_IPV4_ONLY,
1105                                                           cancellable,
1106                                                           got_ipv4_addresses, g_object_ref (addr_enum));
1107             }
1108           g_object_unref (resolver);
1109           return;
1110         }
1111
1112       g_object_unref (resolver);
1113     }
1114
1115   sockaddr = init_and_query_next_address (addr_enum);
1116   if (sockaddr == NULL && (addr_enum->state & RESOLVE_STATE_WAITING_ON_IPV4 ||
1117                            addr_enum->state & RESOLVE_STATE_WAITING_ON_IPV6))
1118     {
1119       addr_enum->waiting_task = task;
1120     }
1121   else
1122     {
1123       g_task_return_pointer (task, sockaddr, g_object_unref);
1124       g_object_unref (task);
1125     }
1126 }
1127
1128 static GSocketAddress *
1129 g_network_address_address_enumerator_next_finish (GSocketAddressEnumerator  *enumerator,
1130                                                   GAsyncResult              *result,
1131                                                   GError                   **error)
1132 {
1133   g_return_val_if_fail (g_task_is_valid (result, enumerator), NULL);
1134
1135   return g_task_propagate_pointer (G_TASK (result), error);
1136 }
1137
1138 static void
1139 _g_network_address_address_enumerator_init (GNetworkAddressAddressEnumerator *enumerator)
1140 {
1141   enumerator->context = g_main_context_ref_thread_default ();
1142 }
1143
1144 static void
1145 _g_network_address_address_enumerator_class_init (GNetworkAddressAddressEnumeratorClass *addrenum_class)
1146 {
1147   GObjectClass *object_class = G_OBJECT_CLASS (addrenum_class);
1148   GSocketAddressEnumeratorClass *enumerator_class =
1149     G_SOCKET_ADDRESS_ENUMERATOR_CLASS (addrenum_class);
1150
1151   enumerator_class->next = g_network_address_address_enumerator_next;
1152   enumerator_class->next_async = g_network_address_address_enumerator_next_async;
1153   enumerator_class->next_finish = g_network_address_address_enumerator_next_finish;
1154   object_class->finalize = g_network_address_address_enumerator_finalize;
1155 }
1156
1157 static GSocketAddressEnumerator *
1158 g_network_address_connectable_enumerate (GSocketConnectable *connectable)
1159 {
1160   GNetworkAddressAddressEnumerator *addr_enum;
1161
1162   addr_enum = g_object_new (G_TYPE_NETWORK_ADDRESS_ADDRESS_ENUMERATOR, NULL);
1163   addr_enum->addr = g_object_ref (G_NETWORK_ADDRESS (connectable));
1164
1165   return (GSocketAddressEnumerator *)addr_enum;
1166 }
1167
1168 static GSocketAddressEnumerator *
1169 g_network_address_connectable_proxy_enumerate (GSocketConnectable *connectable)
1170 {
1171   GNetworkAddress *self = G_NETWORK_ADDRESS (connectable);
1172   GSocketAddressEnumerator *proxy_enum;
1173   gchar *uri;
1174
1175   uri = g_uri_join (G_URI_FLAGS_NONE,
1176                     self->priv->scheme ? self->priv->scheme : "none",
1177                     NULL,
1178                     self->priv->hostname,
1179                     self->priv->port,
1180                     "",
1181                     NULL,
1182                     NULL);
1183
1184   proxy_enum = g_object_new (G_TYPE_PROXY_ADDRESS_ENUMERATOR,
1185                              "connectable", connectable,
1186                              "uri", uri,
1187                              NULL);
1188
1189   g_free (uri);
1190
1191   return proxy_enum;
1192 }
1193
1194 static gchar *
1195 g_network_address_connectable_to_string (GSocketConnectable *connectable)
1196 {
1197   GNetworkAddress *addr;
1198   const gchar *scheme;
1199   guint16 port;
1200   GString *out;  /* owned */
1201
1202   addr = G_NETWORK_ADDRESS (connectable);
1203   out = g_string_new ("");
1204
1205   scheme = g_network_address_get_scheme (addr);
1206   if (scheme != NULL)
1207     g_string_append_printf (out, "%s:", scheme);
1208
1209   g_string_append (out, g_network_address_get_hostname (addr));
1210
1211   port = g_network_address_get_port (addr);
1212   if (port != 0)
1213     g_string_append_printf (out, ":%u", port);
1214
1215   return g_string_free (out, FALSE);
1216 }