mirror of
https://gitlab.gnome.org/GNOME/glib.git
synced 2024-11-06 17:36:14 +01:00
82c764ce2e
I had thought that because `g_source_destroy()` was called for the two sources (cancel and timeout) in the `GTask` finalize function for a threaded resolver operation, that it would be fine to use a plain pointer in the source callbacks to point to the `GTask`. That turns out to not be true: because the source callbacks are executed in the GLib worker thread, and the `GTask` can be finalized in another thread, it’s possible for a source callback (e.g. `cancelled_cb()`) to be scheduled in the worker thread, then for the `GTask` to be finalized, and then the source callback to continue execution and find itself doing a use-after-free. Fix that by using a weak ref to the `GTask` in the source callbacks, rather than a plain pointer. Signed-off-by: Philip Withnall <philip@tecnocode.co.uk> Fixes: #3105
1665 lines
52 KiB
C
1665 lines
52 KiB
C
/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
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/* GIO - GLib Input, Output and Streaming Library
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*
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* Copyright (C) 2008 Red Hat, Inc.
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* Copyright (C) 2018 Igalia S.L.
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*
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* SPDX-License-Identifier: LGPL-2.1-or-later
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
|
||
* License as published by the Free Software Foundation; either
|
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* version 2.1 of the License, or (at your option) any later version.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||
* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General
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* Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
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*/
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||
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#include "config.h"
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#include <glib.h>
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#include "glibintl.h"
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#include <stdio.h>
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#include <string.h>
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#include "glib/glib-private.h"
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#include "gthreadedresolver.h"
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#include "gnetworkingprivate.h"
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#include "gcancellable.h"
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#include "ginetaddress.h"
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#include "ginetsocketaddress.h"
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#include "gtask.h"
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#include "gsocketaddress.h"
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#include "gsrvtarget.h"
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/*
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* GThreadedResolver is a threaded wrapper around the system libc’s
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* `getaddrinfo()`.
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*
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* It has to be threaded, as `getaddrinfo()` is synchronous. libc does provide
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* `getaddrinfo_a()` as an asynchronous version of `getaddrinfo()`, but it does
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* not integrate with a poll loop. It requires use of sigevent to notify of
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* completion of an asynchronous operation. That either emits a signal, or calls
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* a callback function in a newly spawned thread.
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*
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* A signal (`SIGEV_SIGNAL`) can’t be used for completion as (aside from being
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* another expensive round trip into the kernel) GLib cannot pick a `SIG*`
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* number which is guaranteed to not be in use elsewhere in the process. Various
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* other things could be interfering with signal dispositions, such as gdb or
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* other libraries in the process. Using a `signalfd()`
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* [cannot improve this situation](https://ldpreload.com/blog/signalfd-is-useless).
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*
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* A callback function in a newly spawned thread (`SIGEV_THREAD`) could be used,
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* but that is very expensive. Internally, glibc currently also just implements
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* `getaddrinfo_a()`
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* [using its own thread pool](https://github.com/bminor/glibc/blob/master/resolv/gai_misc.c),
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* and then
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* [spawns an additional thread for each completion callback](https://github.com/bminor/glibc/blob/master/resolv/gai_notify.c).
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* That is very expensive.
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*
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* No other appropriate sigevent callback types
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* [currently exist](https://sourceware.org/bugzilla/show_bug.cgi?id=30287), and
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* [others agree that sigevent is not great](http://davmac.org/davpage/linux/async-io.html#posixaio).
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*
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* Hence, #GThreadedResolver calls the normal synchronous `getaddrinfo()` in its
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* own thread pool. Previously, #GThreadedResolver used the thread pool which is
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* internal to #GTask by calling g_task_run_in_thread(). That lead to exhaustion
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* of the #GTask thread pool in some situations, though, as DNS lookups are
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* quite frequent leaf operations in some use cases. Now, #GThreadedResolver
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* uses its own private thread pool.
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*
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* This is similar to what
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* [libasyncns](http://git.0pointer.net/libasyncns.git/tree/libasyncns/asyncns.h)
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* and other multi-threaded users of `getaddrinfo()` do.
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*/
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struct _GThreadedResolver
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{
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GResolver parent_instance;
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GThreadPool *thread_pool; /* (owned) */
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};
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G_DEFINE_TYPE (GThreadedResolver, g_threaded_resolver, G_TYPE_RESOLVER)
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static void run_task_in_thread_pool_async (GThreadedResolver *self,
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GTask *task);
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static void run_task_in_thread_pool_sync (GThreadedResolver *self,
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GTask *task);
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static void threaded_resolver_worker_cb (gpointer task_data,
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gpointer user_data);
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static void
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g_threaded_resolver_init (GThreadedResolver *self)
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{
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self->thread_pool = g_thread_pool_new_full (threaded_resolver_worker_cb,
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self,
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(GDestroyNotify) g_object_unref,
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20,
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FALSE,
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NULL);
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}
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static void
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g_threaded_resolver_finalize (GObject *object)
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{
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GThreadedResolver *self = G_THREADED_RESOLVER (object);
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g_thread_pool_free (self->thread_pool, TRUE, FALSE);
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self->thread_pool = NULL;
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G_OBJECT_CLASS (g_threaded_resolver_parent_class)->finalize (object);
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}
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static GResolverError
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g_resolver_error_from_addrinfo_error (gint err)
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{
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switch (err)
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{
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||
case EAI_FAIL:
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#if defined(EAI_NODATA) && (EAI_NODATA != EAI_NONAME)
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case EAI_NODATA:
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#endif
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case EAI_NONAME:
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return G_RESOLVER_ERROR_NOT_FOUND;
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case EAI_AGAIN:
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return G_RESOLVER_ERROR_TEMPORARY_FAILURE;
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default:
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return G_RESOLVER_ERROR_INTERNAL;
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}
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}
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typedef struct {
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enum {
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LOOKUP_BY_NAME,
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LOOKUP_BY_ADDRESS,
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LOOKUP_RECORDS,
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} lookup_type;
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union {
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struct {
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char *hostname;
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int address_family;
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} lookup_by_name;
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struct {
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GInetAddress *address; /* (owned) */
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} lookup_by_address;
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struct {
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char *rrname;
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GResolverRecordType record_type;
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} lookup_records;
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};
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GCond cond; /* used for signalling completion of the task when running it sync */
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GMutex lock;
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GSource *timeout_source; /* (nullable) (owned) */
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GSource *cancellable_source; /* (nullable) (owned) */
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/* This enum indicates that a particular code path has claimed the
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* task and is shortly about to call g_task_return_*() on it.
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* This must be accessed with GThreadedResolver.lock held. */
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enum
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{
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NOT_YET,
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COMPLETED, /* libc lookup call has completed successfully or errored */
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TIMED_OUT,
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CANCELLED,
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} will_return;
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/* Whether the thread pool thread executing this lookup has finished executing
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* it and g_task_return_*() has been called on it already.
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* This must be accessed with GThreadedResolver.lock held. */
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gboolean has_returned;
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} LookupData;
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static LookupData *
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lookup_data_new_by_name (const char *hostname,
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int address_family)
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{
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LookupData *data = g_new0 (LookupData, 1);
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data->lookup_type = LOOKUP_BY_NAME;
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g_cond_init (&data->cond);
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g_mutex_init (&data->lock);
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data->lookup_by_name.hostname = g_strdup (hostname);
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data->lookup_by_name.address_family = address_family;
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return g_steal_pointer (&data);
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}
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static LookupData *
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lookup_data_new_by_address (GInetAddress *address)
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{
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LookupData *data = g_new0 (LookupData, 1);
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data->lookup_type = LOOKUP_BY_ADDRESS;
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g_cond_init (&data->cond);
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g_mutex_init (&data->lock);
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data->lookup_by_address.address = g_object_ref (address);
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return g_steal_pointer (&data);
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}
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static LookupData *
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lookup_data_new_records (const gchar *rrname,
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GResolverRecordType record_type)
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{
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LookupData *data = g_new0 (LookupData, 1);
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data->lookup_type = LOOKUP_RECORDS;
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g_cond_init (&data->cond);
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g_mutex_init (&data->lock);
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data->lookup_records.rrname = g_strdup (rrname);
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data->lookup_records.record_type = record_type;
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return g_steal_pointer (&data);
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}
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static void
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lookup_data_free (LookupData *data)
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{
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switch (data->lookup_type) {
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case LOOKUP_BY_NAME:
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g_free (data->lookup_by_name.hostname);
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break;
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case LOOKUP_BY_ADDRESS:
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g_clear_object (&data->lookup_by_address.address);
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break;
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case LOOKUP_RECORDS:
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g_free (data->lookup_records.rrname);
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break;
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default:
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g_assert_not_reached ();
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}
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if (data->timeout_source != NULL)
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{
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g_source_destroy (data->timeout_source);
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g_clear_pointer (&data->timeout_source, g_source_unref);
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}
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if (data->cancellable_source != NULL)
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{
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g_source_destroy (data->cancellable_source);
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g_clear_pointer (&data->cancellable_source, g_source_unref);
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}
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g_mutex_clear (&data->lock);
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g_cond_clear (&data->cond);
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g_free (data);
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}
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static GList *
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do_lookup_by_name (const gchar *hostname,
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int address_family,
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GCancellable *cancellable,
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GError **error)
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{
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struct addrinfo *res = NULL;
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GList *addresses;
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gint retval;
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struct addrinfo addrinfo_hints = { 0 };
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#ifdef AI_ADDRCONFIG
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addrinfo_hints.ai_flags = AI_ADDRCONFIG;
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#endif
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/* socktype and protocol don't actually matter, they just get copied into the
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* returned addrinfo structures (and then we ignore them). But if
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* we leave them unset, we'll get back duplicate answers.
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*/
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addrinfo_hints.ai_socktype = SOCK_STREAM;
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addrinfo_hints.ai_protocol = IPPROTO_TCP;
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addrinfo_hints.ai_family = address_family;
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retval = getaddrinfo (hostname, NULL, &addrinfo_hints, &res);
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if (retval == 0)
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{
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struct addrinfo *ai;
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GSocketAddress *sockaddr;
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GInetAddress *addr;
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addresses = NULL;
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for (ai = res; ai; ai = ai->ai_next)
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{
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sockaddr = g_socket_address_new_from_native (ai->ai_addr, ai->ai_addrlen);
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if (!sockaddr)
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continue;
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if (!G_IS_INET_SOCKET_ADDRESS (sockaddr))
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{
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g_clear_object (&sockaddr);
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continue;
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}
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addr = g_object_ref (g_inet_socket_address_get_address ((GInetSocketAddress *)sockaddr));
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addresses = g_list_prepend (addresses, addr);
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g_object_unref (sockaddr);
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}
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g_clear_pointer (&res, freeaddrinfo);
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if (addresses != NULL)
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{
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addresses = g_list_reverse (addresses);
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return g_steal_pointer (&addresses);
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}
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else
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{
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/* All addresses failed to be converted to GSocketAddresses. */
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g_set_error (error,
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G_RESOLVER_ERROR,
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G_RESOLVER_ERROR_NOT_FOUND,
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_("Error resolving “%s”: %s"),
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hostname,
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_("No valid addresses were found"));
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return NULL;
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}
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}
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else
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{
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#ifdef G_OS_WIN32
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gchar *error_message = g_win32_error_message (WSAGetLastError ());
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#else
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gchar *error_message = g_locale_to_utf8 (gai_strerror (retval), -1, NULL, NULL, NULL);
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if (error_message == NULL)
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error_message = g_strdup ("[Invalid UTF-8]");
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#endif
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g_clear_pointer (&res, freeaddrinfo);
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g_set_error (error,
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G_RESOLVER_ERROR,
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g_resolver_error_from_addrinfo_error (retval),
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_("Error resolving “%s”: %s"),
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hostname, error_message);
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g_free (error_message);
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return NULL;
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}
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}
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static GList *
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lookup_by_name (GResolver *resolver,
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const gchar *hostname,
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GCancellable *cancellable,
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GError **error)
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{
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GThreadedResolver *self = G_THREADED_RESOLVER (resolver);
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GTask *task;
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GList *addresses;
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LookupData *data;
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data = lookup_data_new_by_name (hostname, AF_UNSPEC);
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task = g_task_new (resolver, cancellable, NULL, NULL);
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g_task_set_source_tag (task, lookup_by_name);
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g_task_set_name (task, "[gio] resolver lookup");
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g_task_set_task_data (task, g_steal_pointer (&data), (GDestroyNotify) lookup_data_free);
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run_task_in_thread_pool_sync (self, task);
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addresses = g_task_propagate_pointer (task, error);
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g_object_unref (task);
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return addresses;
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}
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|
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static int
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flags_to_family (GResolverNameLookupFlags flags)
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{
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int address_family = AF_UNSPEC;
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if (flags & G_RESOLVER_NAME_LOOKUP_FLAGS_IPV4_ONLY)
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address_family = AF_INET;
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if (flags & G_RESOLVER_NAME_LOOKUP_FLAGS_IPV6_ONLY)
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{
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address_family = AF_INET6;
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/* You can only filter by one family at a time */
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g_return_val_if_fail (!(flags & G_RESOLVER_NAME_LOOKUP_FLAGS_IPV4_ONLY), address_family);
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}
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return address_family;
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}
|
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|
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static GList *
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lookup_by_name_with_flags (GResolver *resolver,
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const gchar *hostname,
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GResolverNameLookupFlags flags,
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GCancellable *cancellable,
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GError **error)
|
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{
|
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GThreadedResolver *self = G_THREADED_RESOLVER (resolver);
|
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GTask *task;
|
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GList *addresses;
|
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LookupData *data;
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data = lookup_data_new_by_name (hostname, flags_to_family (flags));
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task = g_task_new (resolver, cancellable, NULL, NULL);
|
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g_task_set_source_tag (task, lookup_by_name_with_flags);
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g_task_set_name (task, "[gio] resolver lookup");
|
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g_task_set_task_data (task, g_steal_pointer (&data), (GDestroyNotify) lookup_data_free);
|
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|
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run_task_in_thread_pool_sync (self, task);
|
||
|
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addresses = g_task_propagate_pointer (task, error);
|
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g_object_unref (task);
|
||
|
||
return addresses;
|
||
}
|
||
|
||
static void
|
||
lookup_by_name_with_flags_async (GResolver *resolver,
|
||
const gchar *hostname,
|
||
GResolverNameLookupFlags flags,
|
||
GCancellable *cancellable,
|
||
GAsyncReadyCallback callback,
|
||
gpointer user_data)
|
||
{
|
||
GThreadedResolver *self = G_THREADED_RESOLVER (resolver);
|
||
GTask *task;
|
||
LookupData *data;
|
||
|
||
data = lookup_data_new_by_name (hostname, flags_to_family (flags));
|
||
task = g_task_new (resolver, cancellable, callback, user_data);
|
||
|
||
g_debug ("%s: starting new lookup for %s with GTask %p, LookupData %p",
|
||
G_STRFUNC, hostname, task, data);
|
||
|
||
g_task_set_source_tag (task, lookup_by_name_with_flags_async);
|
||
g_task_set_name (task, "[gio] resolver lookup");
|
||
g_task_set_task_data (task, g_steal_pointer (&data), (GDestroyNotify) lookup_data_free);
|
||
|
||
run_task_in_thread_pool_async (self, task);
|
||
|
||
g_object_unref (task);
|
||
}
|
||
|
||
static void
|
||
lookup_by_name_async (GResolver *resolver,
|
||
const gchar *hostname,
|
||
GCancellable *cancellable,
|
||
GAsyncReadyCallback callback,
|
||
gpointer user_data)
|
||
{
|
||
lookup_by_name_with_flags_async (resolver,
|
||
hostname,
|
||
G_RESOLVER_NAME_LOOKUP_FLAGS_DEFAULT,
|
||
cancellable,
|
||
callback,
|
||
user_data);
|
||
}
|
||
|
||
static GList *
|
||
lookup_by_name_finish (GResolver *resolver,
|
||
GAsyncResult *result,
|
||
GError **error)
|
||
{
|
||
g_return_val_if_fail (g_task_is_valid (result, resolver), NULL);
|
||
|
||
return g_task_propagate_pointer (G_TASK (result), error);
|
||
}
|
||
|
||
static GList *
|
||
lookup_by_name_with_flags_finish (GResolver *resolver,
|
||
GAsyncResult *result,
|
||
GError **error)
|
||
{
|
||
g_return_val_if_fail (g_task_is_valid (result, resolver), NULL);
|
||
|
||
return g_task_propagate_pointer (G_TASK (result), error);
|
||
}
|
||
|
||
static gchar *
|
||
do_lookup_by_address (GInetAddress *address,
|
||
GCancellable *cancellable,
|
||
GError **error)
|
||
{
|
||
struct sockaddr_storage sockaddr_address;
|
||
gsize sockaddr_address_size;
|
||
GSocketAddress *gsockaddr;
|
||
gchar name[NI_MAXHOST];
|
||
gint retval;
|
||
|
||
gsockaddr = g_inet_socket_address_new (address, 0);
|
||
g_socket_address_to_native (gsockaddr, (struct sockaddr *)&sockaddr_address,
|
||
sizeof (sockaddr_address), NULL);
|
||
sockaddr_address_size = g_socket_address_get_native_size (gsockaddr);
|
||
g_object_unref (gsockaddr);
|
||
|
||
retval = getnameinfo ((struct sockaddr *) &sockaddr_address, sockaddr_address_size,
|
||
name, sizeof (name), NULL, 0, NI_NAMEREQD);
|
||
if (retval == 0)
|
||
return g_strdup (name);
|
||
else
|
||
{
|
||
gchar *phys;
|
||
|
||
#ifdef G_OS_WIN32
|
||
gchar *error_message = g_win32_error_message (WSAGetLastError ());
|
||
#else
|
||
gchar *error_message = g_locale_to_utf8 (gai_strerror (retval), -1, NULL, NULL, NULL);
|
||
if (error_message == NULL)
|
||
error_message = g_strdup ("[Invalid UTF-8]");
|
||
#endif
|
||
|
||
phys = g_inet_address_to_string (address);
|
||
g_set_error (error,
|
||
G_RESOLVER_ERROR,
|
||
g_resolver_error_from_addrinfo_error (retval),
|
||
_("Error reverse-resolving “%s”: %s"),
|
||
phys ? phys : "(unknown)",
|
||
error_message);
|
||
g_free (phys);
|
||
g_free (error_message);
|
||
|
||
return NULL;
|
||
}
|
||
}
|
||
|
||
static gchar *
|
||
lookup_by_address (GResolver *resolver,
|
||
GInetAddress *address,
|
||
GCancellable *cancellable,
|
||
GError **error)
|
||
{
|
||
GThreadedResolver *self = G_THREADED_RESOLVER (resolver);
|
||
LookupData *data = NULL;
|
||
GTask *task;
|
||
gchar *name;
|
||
|
||
data = lookup_data_new_by_address (address);
|
||
task = g_task_new (resolver, cancellable, NULL, NULL);
|
||
g_task_set_source_tag (task, lookup_by_address);
|
||
g_task_set_name (task, "[gio] resolver lookup");
|
||
g_task_set_task_data (task, g_steal_pointer (&data), (GDestroyNotify) lookup_data_free);
|
||
|
||
run_task_in_thread_pool_sync (self, task);
|
||
|
||
name = g_task_propagate_pointer (task, error);
|
||
g_object_unref (task);
|
||
|
||
return name;
|
||
}
|
||
|
||
static void
|
||
lookup_by_address_async (GResolver *resolver,
|
||
GInetAddress *address,
|
||
GCancellable *cancellable,
|
||
GAsyncReadyCallback callback,
|
||
gpointer user_data)
|
||
{
|
||
GThreadedResolver *self = G_THREADED_RESOLVER (resolver);
|
||
LookupData *data = NULL;
|
||
GTask *task;
|
||
|
||
data = lookup_data_new_by_address (address);
|
||
task = g_task_new (resolver, cancellable, callback, user_data);
|
||
g_task_set_source_tag (task, lookup_by_address_async);
|
||
g_task_set_name (task, "[gio] resolver lookup");
|
||
g_task_set_task_data (task, g_steal_pointer (&data), (GDestroyNotify) lookup_data_free);
|
||
|
||
run_task_in_thread_pool_async (self, task);
|
||
|
||
g_object_unref (task);
|
||
}
|
||
|
||
static gchar *
|
||
lookup_by_address_finish (GResolver *resolver,
|
||
GAsyncResult *result,
|
||
GError **error)
|
||
{
|
||
g_return_val_if_fail (g_task_is_valid (result, resolver), NULL);
|
||
|
||
return g_task_propagate_pointer (G_TASK (result), error);
|
||
}
|
||
|
||
|
||
#if defined(G_OS_UNIX)
|
||
|
||
#if defined __BIONIC__ && !defined BIND_4_COMPAT
|
||
/* Copy from bionic/libc/private/arpa_nameser_compat.h
|
||
* and bionic/libc/private/arpa_nameser.h */
|
||
typedef struct {
|
||
unsigned id :16; /* query identification number */
|
||
#if BYTE_ORDER == BIG_ENDIAN
|
||
/* fields in third byte */
|
||
unsigned qr: 1; /* response flag */
|
||
unsigned opcode: 4; /* purpose of message */
|
||
unsigned aa: 1; /* authoritative answer */
|
||
unsigned tc: 1; /* truncated message */
|
||
unsigned rd: 1; /* recursion desired */
|
||
/* fields in fourth byte */
|
||
unsigned ra: 1; /* recursion available */
|
||
unsigned unused :1; /* unused bits (MBZ as of 4.9.3a3) */
|
||
unsigned ad: 1; /* authentic data from named */
|
||
unsigned cd: 1; /* checking disabled by resolver */
|
||
unsigned rcode :4; /* response code */
|
||
#endif
|
||
#if BYTE_ORDER == LITTLE_ENDIAN || BYTE_ORDER == PDP_ENDIAN
|
||
/* fields in third byte */
|
||
unsigned rd :1; /* recursion desired */
|
||
unsigned tc :1; /* truncated message */
|
||
unsigned aa :1; /* authoritative answer */
|
||
unsigned opcode :4; /* purpose of message */
|
||
unsigned qr :1; /* response flag */
|
||
/* fields in fourth byte */
|
||
unsigned rcode :4; /* response code */
|
||
unsigned cd: 1; /* checking disabled by resolver */
|
||
unsigned ad: 1; /* authentic data from named */
|
||
unsigned unused :1; /* unused bits (MBZ as of 4.9.3a3) */
|
||
unsigned ra :1; /* recursion available */
|
||
#endif
|
||
/* remaining bytes */
|
||
unsigned qdcount :16; /* number of question entries */
|
||
unsigned ancount :16; /* number of answer entries */
|
||
unsigned nscount :16; /* number of authority entries */
|
||
unsigned arcount :16; /* number of resource entries */
|
||
} HEADER;
|
||
|
||
#define NS_INT32SZ 4 /* #/bytes of data in a uint32_t */
|
||
#define NS_INT16SZ 2 /* #/bytes of data in a uint16_t */
|
||
|
||
#define NS_GET16(s, cp) do { \
|
||
const u_char *t_cp = (const u_char *)(cp); \
|
||
(s) = ((uint16_t)t_cp[0] << 8) \
|
||
| ((uint16_t)t_cp[1]) \
|
||
; \
|
||
(cp) += NS_INT16SZ; \
|
||
} while (/*CONSTCOND*/0)
|
||
|
||
#define NS_GET32(l, cp) do { \
|
||
const u_char *t_cp = (const u_char *)(cp); \
|
||
(l) = ((uint32_t)t_cp[0] << 24) \
|
||
| ((uint32_t)t_cp[1] << 16) \
|
||
| ((uint32_t)t_cp[2] << 8) \
|
||
| ((uint32_t)t_cp[3]) \
|
||
; \
|
||
(cp) += NS_INT32SZ; \
|
||
} while (/*CONSTCOND*/0)
|
||
|
||
#define GETSHORT NS_GET16
|
||
#define GETLONG NS_GET32
|
||
|
||
#define C_IN 1
|
||
|
||
/* From bionic/libc/private/resolv_private.h */
|
||
int dn_expand(const u_char *, const u_char *, const u_char *, char *, int);
|
||
#define dn_skipname __dn_skipname
|
||
int dn_skipname(const u_char *, const u_char *);
|
||
|
||
/* From bionic/libc/private/arpa_nameser_compat.h */
|
||
#define T_MX ns_t_mx
|
||
#define T_TXT ns_t_txt
|
||
#define T_SOA ns_t_soa
|
||
#define T_NS ns_t_ns
|
||
|
||
/* From bionic/libc/private/arpa_nameser.h */
|
||
typedef enum __ns_type {
|
||
ns_t_invalid = 0, /* Cookie. */
|
||
ns_t_a = 1, /* Host address. */
|
||
ns_t_ns = 2, /* Authoritative server. */
|
||
ns_t_md = 3, /* Mail destination. */
|
||
ns_t_mf = 4, /* Mail forwarder. */
|
||
ns_t_cname = 5, /* Canonical name. */
|
||
ns_t_soa = 6, /* Start of authority zone. */
|
||
ns_t_mb = 7, /* Mailbox domain name. */
|
||
ns_t_mg = 8, /* Mail group member. */
|
||
ns_t_mr = 9, /* Mail rename name. */
|
||
ns_t_null = 10, /* Null resource record. */
|
||
ns_t_wks = 11, /* Well known service. */
|
||
ns_t_ptr = 12, /* Domain name pointer. */
|
||
ns_t_hinfo = 13, /* Host information. */
|
||
ns_t_minfo = 14, /* Mailbox information. */
|
||
ns_t_mx = 15, /* Mail routing information. */
|
||
ns_t_txt = 16, /* Text strings. */
|
||
ns_t_rp = 17, /* Responsible person. */
|
||
ns_t_afsdb = 18, /* AFS cell database. */
|
||
ns_t_x25 = 19, /* X_25 calling address. */
|
||
ns_t_isdn = 20, /* ISDN calling address. */
|
||
ns_t_rt = 21, /* Router. */
|
||
ns_t_nsap = 22, /* NSAP address. */
|
||
ns_t_nsap_ptr = 23, /* Reverse NSAP lookup (deprecated). */
|
||
ns_t_sig = 24, /* Security signature. */
|
||
ns_t_key = 25, /* Security key. */
|
||
ns_t_px = 26, /* X.400 mail mapping. */
|
||
ns_t_gpos = 27, /* Geographical position (withdrawn). */
|
||
ns_t_aaaa = 28, /* Ip6 Address. */
|
||
ns_t_loc = 29, /* Location Information. */
|
||
ns_t_nxt = 30, /* Next domain (security). */
|
||
ns_t_eid = 31, /* Endpoint identifier. */
|
||
ns_t_nimloc = 32, /* Nimrod Locator. */
|
||
ns_t_srv = 33, /* Server Selection. */
|
||
ns_t_atma = 34, /* ATM Address */
|
||
ns_t_naptr = 35, /* Naming Authority PoinTeR */
|
||
ns_t_kx = 36, /* Key Exchange */
|
||
ns_t_cert = 37, /* Certification record */
|
||
ns_t_a6 = 38, /* IPv6 address (deprecates AAAA) */
|
||
ns_t_dname = 39, /* Non-terminal DNAME (for IPv6) */
|
||
ns_t_sink = 40, /* Kitchen sink (experimental) */
|
||
ns_t_opt = 41, /* EDNS0 option (meta-RR) */
|
||
ns_t_apl = 42, /* Address prefix list (RFC 3123) */
|
||
ns_t_tkey = 249, /* Transaction key */
|
||
ns_t_tsig = 250, /* Transaction signature. */
|
||
ns_t_ixfr = 251, /* Incremental zone transfer. */
|
||
ns_t_axfr = 252, /* Transfer zone of authority. */
|
||
ns_t_mailb = 253, /* Transfer mailbox records. */
|
||
ns_t_maila = 254, /* Transfer mail agent records. */
|
||
ns_t_any = 255, /* Wildcard match. */
|
||
ns_t_zxfr = 256, /* BIND-specific, nonstandard. */
|
||
ns_t_max = 65536
|
||
} ns_type;
|
||
|
||
#endif /* __BIONIC__ */
|
||
|
||
/* Wrapper around dn_expand() which does associated length checks and returns
|
||
* errors as #GError. */
|
||
static gboolean
|
||
expand_name (const gchar *rrname,
|
||
const guint8 *answer,
|
||
const guint8 *end,
|
||
const guint8 **p,
|
||
gchar *namebuf,
|
||
gsize namebuf_len,
|
||
GError **error)
|
||
{
|
||
int expand_result;
|
||
|
||
expand_result = dn_expand (answer, end, *p, namebuf, namebuf_len);
|
||
if (expand_result < 0 || end - *p < expand_result)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the placeholder is a DNS record type, such as ‘MX’ or ‘SRV’ */
|
||
_("Error parsing DNS %s record: malformed DNS packet"), rrname);
|
||
return FALSE;
|
||
}
|
||
|
||
*p += expand_result;
|
||
|
||
return TRUE;
|
||
}
|
||
|
||
static GVariant *
|
||
parse_res_srv (const guint8 *answer,
|
||
const guint8 *end,
|
||
const guint8 **p,
|
||
GError **error)
|
||
{
|
||
gchar namebuf[1024];
|
||
guint16 priority, weight, port;
|
||
|
||
if (end - *p < 6)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the placeholder is a DNS record type, such as ‘MX’ or ‘SRV’ */
|
||
_("Error parsing DNS %s record: malformed DNS packet"), "SRV");
|
||
return NULL;
|
||
}
|
||
|
||
GETSHORT (priority, *p);
|
||
GETSHORT (weight, *p);
|
||
GETSHORT (port, *p);
|
||
|
||
/* RFC 2782 says (on page 4) that “Unless and until permitted by future
|
||
* standards action, name compression is not to be used for this field.”, so
|
||
* technically we shouldn’t be expanding names here for SRV records.
|
||
*
|
||
* However, other DNS resolvers (such as systemd[1]) do, and it seems in
|
||
* keeping with the principle of being liberal in what you accept and strict
|
||
* in what you emit. It also seems harmless.
|
||
*
|
||
* An earlier version of the RFC, RFC 2052 (now obsolete) specified that name
|
||
* compression *was* to be used for SRV targets[2].
|
||
*
|
||
* See discussion on https://gitlab.gnome.org/GNOME/glib/-/issues/2622.
|
||
*
|
||
* [1]: https://github.com/yuwata/systemd/blob/2d23cc3c07c49722ce93170737b3efd2692a2d08/src/resolve/resolved-dns-packet.c#L1674
|
||
* [2]: https://datatracker.ietf.org/doc/html/rfc2052#page-3
|
||
*/
|
||
if (!expand_name ("SRV", answer, end, p, namebuf, sizeof (namebuf), error))
|
||
return NULL;
|
||
|
||
return g_variant_new ("(qqqs)",
|
||
priority,
|
||
weight,
|
||
port,
|
||
namebuf);
|
||
}
|
||
|
||
static GVariant *
|
||
parse_res_soa (const guint8 *answer,
|
||
const guint8 *end,
|
||
const guint8 **p,
|
||
GError **error)
|
||
{
|
||
gchar mnamebuf[1024];
|
||
gchar rnamebuf[1024];
|
||
guint32 serial, refresh, retry, expire, ttl;
|
||
|
||
if (!expand_name ("SOA", answer, end, p, mnamebuf, sizeof (mnamebuf), error))
|
||
return NULL;
|
||
|
||
if (!expand_name ("SOA", answer, end, p, rnamebuf, sizeof (rnamebuf), error))
|
||
return NULL;
|
||
|
||
if (end - *p < 20)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the placeholder is a DNS record type, such as ‘MX’ or ‘SRV’ */
|
||
_("Error parsing DNS %s record: malformed DNS packet"), "SOA");
|
||
return NULL;
|
||
}
|
||
|
||
GETLONG (serial, *p);
|
||
GETLONG (refresh, *p);
|
||
GETLONG (retry, *p);
|
||
GETLONG (expire, *p);
|
||
GETLONG (ttl, *p);
|
||
|
||
return g_variant_new ("(ssuuuuu)",
|
||
mnamebuf,
|
||
rnamebuf,
|
||
serial,
|
||
refresh,
|
||
retry,
|
||
expire,
|
||
ttl);
|
||
}
|
||
|
||
static GVariant *
|
||
parse_res_ns (const guint8 *answer,
|
||
const guint8 *end,
|
||
const guint8 **p,
|
||
GError **error)
|
||
{
|
||
gchar namebuf[1024];
|
||
|
||
if (!expand_name ("NS", answer, end, p, namebuf, sizeof (namebuf), error))
|
||
return NULL;
|
||
|
||
return g_variant_new ("(s)", namebuf);
|
||
}
|
||
|
||
static GVariant *
|
||
parse_res_mx (const guint8 *answer,
|
||
const guint8 *end,
|
||
const guint8 **p,
|
||
GError **error)
|
||
{
|
||
gchar namebuf[1024];
|
||
guint16 preference;
|
||
|
||
if (end - *p < 2)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the placeholder is a DNS record type, such as ‘MX’ or ‘SRV’ */
|
||
_("Error parsing DNS %s record: malformed DNS packet"), "MX");
|
||
return NULL;
|
||
}
|
||
|
||
GETSHORT (preference, *p);
|
||
|
||
if (!expand_name ("MX", answer, end, p, namebuf, sizeof (namebuf), error))
|
||
return NULL;
|
||
|
||
return g_variant_new ("(qs)",
|
||
preference,
|
||
namebuf);
|
||
}
|
||
|
||
static GVariant *
|
||
parse_res_txt (const guint8 *answer,
|
||
const guint8 *end,
|
||
const guint8 **p,
|
||
GError **error)
|
||
{
|
||
GVariant *record;
|
||
GPtrArray *array;
|
||
const guint8 *at = *p;
|
||
gsize len;
|
||
|
||
if (end - *p == 0)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the placeholder is a DNS record type, such as ‘MX’ or ‘SRV’ */
|
||
_("Error parsing DNS %s record: malformed DNS packet"), "TXT");
|
||
return NULL;
|
||
}
|
||
|
||
array = g_ptr_array_new_with_free_func (g_free);
|
||
while (at < end)
|
||
{
|
||
len = *(at++);
|
||
if (len > (gsize) (end - at))
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the placeholder is a DNS record type, such as ‘MX’ or ‘SRV’ */
|
||
_("Error parsing DNS %s record: malformed DNS packet"), "TXT");
|
||
g_ptr_array_free (array, TRUE);
|
||
return NULL;
|
||
}
|
||
|
||
g_ptr_array_add (array, g_strndup ((gchar *)at, len));
|
||
at += len;
|
||
}
|
||
|
||
*p = at;
|
||
record = g_variant_new ("(@as)",
|
||
g_variant_new_strv ((const gchar **)array->pdata, array->len));
|
||
g_ptr_array_free (array, TRUE);
|
||
return record;
|
||
}
|
||
|
||
gint
|
||
g_resolver_record_type_to_rrtype (GResolverRecordType type)
|
||
{
|
||
switch (type)
|
||
{
|
||
case G_RESOLVER_RECORD_SRV:
|
||
return T_SRV;
|
||
case G_RESOLVER_RECORD_TXT:
|
||
return T_TXT;
|
||
case G_RESOLVER_RECORD_SOA:
|
||
return T_SOA;
|
||
case G_RESOLVER_RECORD_NS:
|
||
return T_NS;
|
||
case G_RESOLVER_RECORD_MX:
|
||
return T_MX;
|
||
}
|
||
g_return_val_if_reached (-1);
|
||
}
|
||
|
||
GList *
|
||
g_resolver_records_from_res_query (const gchar *rrname,
|
||
gint rrtype,
|
||
const guint8 *answer,
|
||
gssize len,
|
||
gint herr,
|
||
GError **error)
|
||
{
|
||
uint16_t count;
|
||
gchar namebuf[1024];
|
||
const guint8 *end, *p;
|
||
guint16 type, qclass, rdlength;
|
||
const HEADER *header;
|
||
GList *records;
|
||
GVariant *record;
|
||
gsize len_unsigned;
|
||
GError *parsing_error = NULL;
|
||
|
||
if (len <= 0)
|
||
{
|
||
if (len == 0 || herr == HOST_NOT_FOUND || herr == NO_DATA)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_NOT_FOUND,
|
||
_("No DNS record of the requested type for “%s”"), rrname);
|
||
}
|
||
else if (herr == TRY_AGAIN)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_TEMPORARY_FAILURE,
|
||
_("Temporarily unable to resolve “%s”"), rrname);
|
||
}
|
||
else
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
_("Error resolving “%s”"), rrname);
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
/* We know len ≥ 0 now. */
|
||
len_unsigned = (gsize) len;
|
||
|
||
if (len_unsigned < sizeof (HEADER))
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the first placeholder is a domain name, the
|
||
* second is an error message */
|
||
_("Error resolving “%s”: %s"), rrname, _("Malformed DNS packet"));
|
||
return NULL;
|
||
}
|
||
|
||
records = NULL;
|
||
|
||
header = (HEADER *)answer;
|
||
p = answer + sizeof (HEADER);
|
||
end = answer + len_unsigned;
|
||
|
||
/* Skip query */
|
||
count = ntohs (header->qdcount);
|
||
while (count-- && p < end)
|
||
{
|
||
int expand_result;
|
||
|
||
expand_result = dn_expand (answer, end, p, namebuf, sizeof (namebuf));
|
||
if (expand_result < 0 || end - p < expand_result + 4)
|
||
{
|
||
/* Not possible to recover parsing as the length of the rest of the
|
||
* record is unknown or is too short. */
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the first placeholder is a domain name, the
|
||
* second is an error message */
|
||
_("Error resolving “%s”: %s"), rrname, _("Malformed DNS packet"));
|
||
return NULL;
|
||
}
|
||
|
||
p += expand_result;
|
||
p += 4; /* skip TYPE and CLASS */
|
||
|
||
/* To silence gcc warnings */
|
||
namebuf[0] = namebuf[1];
|
||
}
|
||
|
||
/* Read answers */
|
||
count = ntohs (header->ancount);
|
||
while (count-- && p < end)
|
||
{
|
||
int expand_result;
|
||
|
||
expand_result = dn_expand (answer, end, p, namebuf, sizeof (namebuf));
|
||
if (expand_result < 0 || end - p < expand_result + 10)
|
||
{
|
||
/* Not possible to recover parsing as the length of the rest of the
|
||
* record is unknown or is too short. */
|
||
g_set_error (&parsing_error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the first placeholder is a domain name, the
|
||
* second is an error message */
|
||
_("Error resolving “%s”: %s"), rrname, _("Malformed DNS packet"));
|
||
break;
|
||
}
|
||
|
||
p += expand_result;
|
||
GETSHORT (type, p);
|
||
GETSHORT (qclass, p);
|
||
p += 4; /* ignore the ttl (type=long) value */
|
||
GETSHORT (rdlength, p);
|
||
|
||
if (end - p < rdlength)
|
||
{
|
||
g_set_error (&parsing_error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
/* Translators: the first placeholder is a domain name, the
|
||
* second is an error message */
|
||
_("Error resolving “%s”: %s"), rrname, _("Malformed DNS packet"));
|
||
break;
|
||
}
|
||
|
||
if (type != rrtype || qclass != C_IN)
|
||
{
|
||
p += rdlength;
|
||
continue;
|
||
}
|
||
|
||
switch (rrtype)
|
||
{
|
||
case T_SRV:
|
||
record = parse_res_srv (answer, p + rdlength, &p, &parsing_error);
|
||
break;
|
||
case T_MX:
|
||
record = parse_res_mx (answer, p + rdlength, &p, &parsing_error);
|
||
break;
|
||
case T_SOA:
|
||
record = parse_res_soa (answer, p + rdlength, &p, &parsing_error);
|
||
break;
|
||
case T_NS:
|
||
record = parse_res_ns (answer, p + rdlength, &p, &parsing_error);
|
||
break;
|
||
case T_TXT:
|
||
record = parse_res_txt (answer, p + rdlength, &p, &parsing_error);
|
||
break;
|
||
default:
|
||
g_debug ("Unrecognised DNS record type %u", rrtype);
|
||
record = NULL;
|
||
break;
|
||
}
|
||
|
||
if (record != NULL)
|
||
records = g_list_prepend (records, record);
|
||
|
||
if (parsing_error != NULL)
|
||
break;
|
||
}
|
||
|
||
if (parsing_error != NULL)
|
||
{
|
||
g_propagate_prefixed_error (error, parsing_error, _("Failed to parse DNS response for “%s”: "), rrname);
|
||
g_list_free_full (records, (GDestroyNotify)g_variant_unref);
|
||
return NULL;
|
||
}
|
||
else if (records == NULL)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_NOT_FOUND,
|
||
_("No DNS record of the requested type for “%s”"), rrname);
|
||
|
||
return NULL;
|
||
}
|
||
else
|
||
return records;
|
||
}
|
||
|
||
#elif defined(G_OS_WIN32)
|
||
|
||
static GVariant *
|
||
parse_dns_srv (DNS_RECORD *rec)
|
||
{
|
||
return g_variant_new ("(qqqs)",
|
||
(guint16)rec->Data.SRV.wPriority,
|
||
(guint16)rec->Data.SRV.wWeight,
|
||
(guint16)rec->Data.SRV.wPort,
|
||
rec->Data.SRV.pNameTarget);
|
||
}
|
||
|
||
static GVariant *
|
||
parse_dns_soa (DNS_RECORD *rec)
|
||
{
|
||
return g_variant_new ("(ssuuuuu)",
|
||
rec->Data.SOA.pNamePrimaryServer,
|
||
rec->Data.SOA.pNameAdministrator,
|
||
(guint32)rec->Data.SOA.dwSerialNo,
|
||
(guint32)rec->Data.SOA.dwRefresh,
|
||
(guint32)rec->Data.SOA.dwRetry,
|
||
(guint32)rec->Data.SOA.dwExpire,
|
||
(guint32)rec->Data.SOA.dwDefaultTtl);
|
||
}
|
||
|
||
static GVariant *
|
||
parse_dns_ns (DNS_RECORD *rec)
|
||
{
|
||
return g_variant_new ("(s)", rec->Data.NS.pNameHost);
|
||
}
|
||
|
||
static GVariant *
|
||
parse_dns_mx (DNS_RECORD *rec)
|
||
{
|
||
return g_variant_new ("(qs)",
|
||
(guint16)rec->Data.MX.wPreference,
|
||
rec->Data.MX.pNameExchange);
|
||
}
|
||
|
||
static GVariant *
|
||
parse_dns_txt (DNS_RECORD *rec)
|
||
{
|
||
GVariant *record;
|
||
GPtrArray *array;
|
||
DWORD i;
|
||
|
||
array = g_ptr_array_new ();
|
||
for (i = 0; i < rec->Data.TXT.dwStringCount; i++)
|
||
g_ptr_array_add (array, rec->Data.TXT.pStringArray[i]);
|
||
record = g_variant_new ("(@as)",
|
||
g_variant_new_strv ((const gchar **)array->pdata, array->len));
|
||
g_ptr_array_free (array, TRUE);
|
||
return record;
|
||
}
|
||
|
||
static WORD
|
||
g_resolver_record_type_to_dnstype (GResolverRecordType type)
|
||
{
|
||
switch (type)
|
||
{
|
||
case G_RESOLVER_RECORD_SRV:
|
||
return DNS_TYPE_SRV;
|
||
case G_RESOLVER_RECORD_TXT:
|
||
return DNS_TYPE_TEXT;
|
||
case G_RESOLVER_RECORD_SOA:
|
||
return DNS_TYPE_SOA;
|
||
case G_RESOLVER_RECORD_NS:
|
||
return DNS_TYPE_NS;
|
||
case G_RESOLVER_RECORD_MX:
|
||
return DNS_TYPE_MX;
|
||
}
|
||
g_return_val_if_reached (-1);
|
||
}
|
||
|
||
static GList *
|
||
g_resolver_records_from_DnsQuery (const gchar *rrname,
|
||
WORD dnstype,
|
||
DNS_STATUS status,
|
||
DNS_RECORD *results,
|
||
GError **error)
|
||
{
|
||
DNS_RECORD *rec;
|
||
gpointer record;
|
||
GList *records;
|
||
|
||
if (status != ERROR_SUCCESS)
|
||
{
|
||
if (status == DNS_ERROR_RCODE_NAME_ERROR)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_NOT_FOUND,
|
||
_("No DNS record of the requested type for “%s”"), rrname);
|
||
}
|
||
else if (status == DNS_ERROR_RCODE_SERVER_FAILURE)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_TEMPORARY_FAILURE,
|
||
_("Temporarily unable to resolve “%s”"), rrname);
|
||
}
|
||
else
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
_("Error resolving “%s”"), rrname);
|
||
}
|
||
|
||
return NULL;
|
||
}
|
||
|
||
records = NULL;
|
||
for (rec = results; rec; rec = rec->pNext)
|
||
{
|
||
if (rec->wType != dnstype)
|
||
continue;
|
||
switch (dnstype)
|
||
{
|
||
case DNS_TYPE_SRV:
|
||
record = parse_dns_srv (rec);
|
||
break;
|
||
case DNS_TYPE_SOA:
|
||
record = parse_dns_soa (rec);
|
||
break;
|
||
case DNS_TYPE_NS:
|
||
record = parse_dns_ns (rec);
|
||
break;
|
||
case DNS_TYPE_MX:
|
||
record = parse_dns_mx (rec);
|
||
break;
|
||
case DNS_TYPE_TEXT:
|
||
record = parse_dns_txt (rec);
|
||
break;
|
||
default:
|
||
g_warn_if_reached ();
|
||
record = NULL;
|
||
break;
|
||
}
|
||
if (record != NULL)
|
||
records = g_list_prepend (records, g_variant_ref_sink (record));
|
||
}
|
||
|
||
if (records == NULL)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_NOT_FOUND,
|
||
_("No DNS record of the requested type for “%s”"), rrname);
|
||
|
||
return NULL;
|
||
}
|
||
else
|
||
return records;
|
||
}
|
||
|
||
#endif
|
||
|
||
static void
|
||
free_records (GList *records)
|
||
{
|
||
g_list_free_full (records, (GDestroyNotify) g_variant_unref);
|
||
}
|
||
|
||
#if defined(G_OS_UNIX)
|
||
#ifdef __BIONIC__
|
||
#ifndef C_IN
|
||
#define C_IN 1
|
||
#endif
|
||
int res_query(const char *, int, int, u_char *, int);
|
||
#endif
|
||
#endif
|
||
|
||
static GList *
|
||
do_lookup_records (const gchar *rrname,
|
||
GResolverRecordType record_type,
|
||
GCancellable *cancellable,
|
||
GError **error)
|
||
{
|
||
GList *records;
|
||
|
||
#if defined(G_OS_UNIX)
|
||
gint len = 512;
|
||
gint herr;
|
||
GByteArray *answer;
|
||
gint rrtype;
|
||
|
||
#ifdef HAVE_RES_NQUERY
|
||
/* Load the resolver state. This is done once per worker thread, and the
|
||
* #GResolver::reload signal is ignored (since we always reload). This could
|
||
* be improved by having an explicit worker thread pool, with each thread
|
||
* containing some state which is initialised at thread creation time and
|
||
* updated in response to #GResolver::reload.
|
||
*
|
||
* What we have currently is not particularly worse than using res_query() in
|
||
* worker threads, since it would transparently call res_init() for each new
|
||
* worker thread. (Although the workers would get reused by the
|
||
* #GThreadPool.)
|
||
*
|
||
* FreeBSD requires the state to be zero-filled before calling res_ninit(). */
|
||
struct __res_state res = { 0, };
|
||
if (res_ninit (&res) != 0)
|
||
{
|
||
g_set_error (error, G_RESOLVER_ERROR, G_RESOLVER_ERROR_INTERNAL,
|
||
_("Error resolving “%s”"), rrname);
|
||
return NULL;
|
||
}
|
||
#endif
|
||
|
||
rrtype = g_resolver_record_type_to_rrtype (record_type);
|
||
answer = g_byte_array_new ();
|
||
for (;;)
|
||
{
|
||
g_byte_array_set_size (answer, len * 2);
|
||
#if defined(HAVE_RES_NQUERY)
|
||
len = res_nquery (&res, rrname, C_IN, rrtype, answer->data, answer->len);
|
||
#else
|
||
len = res_query (rrname, C_IN, rrtype, answer->data, answer->len);
|
||
#endif
|
||
|
||
/* If answer fit in the buffer then we're done */
|
||
if (len < 0 || len < (gint)answer->len)
|
||
break;
|
||
|
||
/*
|
||
* On overflow some res_query's return the length needed, others
|
||
* return the full length entered. This code works in either case.
|
||
*/
|
||
}
|
||
|
||
herr = h_errno;
|
||
records = g_resolver_records_from_res_query (rrname, rrtype, answer->data, len, herr, error);
|
||
g_byte_array_free (answer, TRUE);
|
||
|
||
#ifdef HAVE_RES_NQUERY
|
||
|
||
#if defined(HAVE_RES_NDESTROY)
|
||
res_ndestroy (&res);
|
||
#elif defined(HAVE_RES_NCLOSE)
|
||
res_nclose (&res);
|
||
#elif defined(HAVE_RES_NINIT)
|
||
#error "Your platform has res_ninit() but not res_nclose() or res_ndestroy(). Please file a bug at https://gitlab.gnome.org/GNOME/glib/issues/new"
|
||
#endif
|
||
|
||
#endif /* HAVE_RES_NQUERY */
|
||
|
||
#else
|
||
|
||
DNS_STATUS status;
|
||
DNS_RECORD *results = NULL;
|
||
WORD dnstype;
|
||
|
||
dnstype = g_resolver_record_type_to_dnstype (record_type);
|
||
status = DnsQuery_A (rrname, dnstype, DNS_QUERY_STANDARD, NULL, &results, NULL);
|
||
records = g_resolver_records_from_DnsQuery (rrname, dnstype, status, results, error);
|
||
if (results != NULL)
|
||
DnsRecordListFree (results, DnsFreeRecordList);
|
||
|
||
#endif
|
||
|
||
return g_steal_pointer (&records);
|
||
}
|
||
|
||
static GList *
|
||
lookup_records (GResolver *resolver,
|
||
const gchar *rrname,
|
||
GResolverRecordType record_type,
|
||
GCancellable *cancellable,
|
||
GError **error)
|
||
{
|
||
GThreadedResolver *self = G_THREADED_RESOLVER (resolver);
|
||
GTask *task;
|
||
GList *records;
|
||
LookupData *data = NULL;
|
||
|
||
task = g_task_new (resolver, cancellable, NULL, NULL);
|
||
g_task_set_source_tag (task, lookup_records);
|
||
g_task_set_name (task, "[gio] resolver lookup records");
|
||
|
||
data = lookup_data_new_records (rrname, record_type);
|
||
g_task_set_task_data (task, g_steal_pointer (&data), (GDestroyNotify) lookup_data_free);
|
||
|
||
run_task_in_thread_pool_sync (self, task);
|
||
|
||
records = g_task_propagate_pointer (task, error);
|
||
g_object_unref (task);
|
||
|
||
return records;
|
||
}
|
||
|
||
static void
|
||
lookup_records_async (GResolver *resolver,
|
||
const char *rrname,
|
||
GResolverRecordType record_type,
|
||
GCancellable *cancellable,
|
||
GAsyncReadyCallback callback,
|
||
gpointer user_data)
|
||
{
|
||
GThreadedResolver *self = G_THREADED_RESOLVER (resolver);
|
||
GTask *task;
|
||
LookupData *data = NULL;
|
||
|
||
task = g_task_new (resolver, cancellable, callback, user_data);
|
||
g_task_set_source_tag (task, lookup_records_async);
|
||
g_task_set_name (task, "[gio] resolver lookup records");
|
||
|
||
data = lookup_data_new_records (rrname, record_type);
|
||
g_task_set_task_data (task, g_steal_pointer (&data), (GDestroyNotify) lookup_data_free);
|
||
|
||
run_task_in_thread_pool_async (self, task);
|
||
|
||
g_object_unref (task);
|
||
}
|
||
|
||
static GList *
|
||
lookup_records_finish (GResolver *resolver,
|
||
GAsyncResult *result,
|
||
GError **error)
|
||
{
|
||
g_return_val_if_fail (g_task_is_valid (result, resolver), NULL);
|
||
|
||
return g_task_propagate_pointer (G_TASK (result), error);
|
||
}
|
||
|
||
/* Will be called in the GLib worker thread, so must lock all accesses to shared
|
||
* data. */
|
||
static gboolean
|
||
timeout_cb (gpointer user_data)
|
||
{
|
||
GWeakRef *weak_task = user_data;
|
||
GTask *task = NULL; /* (owned) */
|
||
LookupData *data;
|
||
gboolean should_return;
|
||
|
||
task = g_weak_ref_get (weak_task);
|
||
if (task == NULL)
|
||
return G_SOURCE_REMOVE;
|
||
|
||
data = g_task_get_task_data (task);
|
||
|
||
g_mutex_lock (&data->lock);
|
||
|
||
should_return = g_atomic_int_compare_and_exchange (&data->will_return, NOT_YET, TIMED_OUT);
|
||
g_clear_pointer (&data->timeout_source, g_source_unref);
|
||
|
||
g_mutex_unlock (&data->lock);
|
||
|
||
if (should_return)
|
||
g_task_return_new_error (task, G_IO_ERROR, G_IO_ERROR_TIMED_OUT,
|
||
_("Socket I/O timed out"));
|
||
|
||
/* Signal completion of the task. */
|
||
g_mutex_lock (&data->lock);
|
||
data->has_returned = TRUE;
|
||
g_cond_broadcast (&data->cond);
|
||
g_mutex_unlock (&data->lock);
|
||
|
||
g_object_unref (task);
|
||
|
||
return G_SOURCE_REMOVE;
|
||
}
|
||
|
||
/* Will be called in the GLib worker thread, so must lock all accesses to shared
|
||
* data. */
|
||
static gboolean
|
||
cancelled_cb (GCancellable *cancellable,
|
||
gpointer user_data)
|
||
{
|
||
GWeakRef *weak_task = user_data;
|
||
GTask *task = NULL; /* (owned) */
|
||
LookupData *data;
|
||
gboolean should_return;
|
||
|
||
task = g_weak_ref_get (weak_task);
|
||
if (task == NULL)
|
||
return G_SOURCE_REMOVE;
|
||
|
||
data = g_task_get_task_data (task);
|
||
|
||
g_mutex_lock (&data->lock);
|
||
|
||
g_assert (g_cancellable_is_cancelled (cancellable));
|
||
should_return = g_atomic_int_compare_and_exchange (&data->will_return, NOT_YET, CANCELLED);
|
||
g_clear_pointer (&data->cancellable_source, g_source_unref);
|
||
|
||
g_mutex_unlock (&data->lock);
|
||
|
||
if (should_return)
|
||
g_task_return_error_if_cancelled (task);
|
||
|
||
/* Signal completion of the task. */
|
||
g_mutex_lock (&data->lock);
|
||
data->has_returned = TRUE;
|
||
g_cond_broadcast (&data->cond);
|
||
g_mutex_unlock (&data->lock);
|
||
|
||
g_object_unref (task);
|
||
|
||
return G_SOURCE_REMOVE;
|
||
}
|
||
|
||
static void
|
||
weak_ref_clear_and_free (GWeakRef *weak_ref)
|
||
{
|
||
g_weak_ref_clear (weak_ref);
|
||
g_free (weak_ref);
|
||
}
|
||
|
||
static void
|
||
run_task_in_thread_pool_async (GThreadedResolver *self,
|
||
GTask *task)
|
||
{
|
||
LookupData *data = g_task_get_task_data (task);
|
||
guint timeout_ms = g_resolver_get_timeout (G_RESOLVER (self));
|
||
GCancellable *cancellable = g_task_get_cancellable (task);
|
||
|
||
g_mutex_lock (&data->lock);
|
||
|
||
g_thread_pool_push (self->thread_pool, g_object_ref (task), NULL);
|
||
|
||
if (timeout_ms != 0)
|
||
{
|
||
GWeakRef *weak_task = g_new0 (GWeakRef, 1);
|
||
g_weak_ref_set (weak_task, task);
|
||
|
||
data->timeout_source = g_timeout_source_new (timeout_ms);
|
||
g_source_set_static_name (data->timeout_source, "[gio] threaded resolver timeout");
|
||
g_source_set_callback (data->timeout_source, G_SOURCE_FUNC (timeout_cb), g_steal_pointer (&weak_task), (GDestroyNotify) weak_ref_clear_and_free);
|
||
g_source_attach (data->timeout_source, GLIB_PRIVATE_CALL (g_get_worker_context) ());
|
||
}
|
||
|
||
if (cancellable != NULL)
|
||
{
|
||
GWeakRef *weak_task = g_new0 (GWeakRef, 1);
|
||
g_weak_ref_set (weak_task, task);
|
||
|
||
data->cancellable_source = g_cancellable_source_new (cancellable);
|
||
g_source_set_static_name (data->cancellable_source, "[gio] threaded resolver cancellable");
|
||
g_source_set_callback (data->cancellable_source, G_SOURCE_FUNC (cancelled_cb), g_steal_pointer (&weak_task), (GDestroyNotify) weak_ref_clear_and_free);
|
||
g_source_attach (data->cancellable_source, GLIB_PRIVATE_CALL (g_get_worker_context) ());
|
||
}
|
||
|
||
g_mutex_unlock (&data->lock);
|
||
}
|
||
|
||
static void
|
||
run_task_in_thread_pool_sync (GThreadedResolver *self,
|
||
GTask *task)
|
||
{
|
||
LookupData *data = g_task_get_task_data (task);
|
||
|
||
run_task_in_thread_pool_async (self, task);
|
||
|
||
g_mutex_lock (&data->lock);
|
||
while (!data->has_returned)
|
||
g_cond_wait (&data->cond, &data->lock);
|
||
g_mutex_unlock (&data->lock);
|
||
}
|
||
|
||
static void
|
||
threaded_resolver_worker_cb (gpointer task_data,
|
||
gpointer user_data)
|
||
{
|
||
GTask *task = G_TASK (g_steal_pointer (&task_data));
|
||
LookupData *data = g_task_get_task_data (task);
|
||
GCancellable *cancellable = g_task_get_cancellable (task);
|
||
GError *local_error = NULL;
|
||
gboolean should_return;
|
||
|
||
switch (data->lookup_type) {
|
||
case LOOKUP_BY_NAME:
|
||
{
|
||
GList *addresses = do_lookup_by_name (data->lookup_by_name.hostname,
|
||
data->lookup_by_name.address_family,
|
||
cancellable,
|
||
&local_error);
|
||
|
||
g_mutex_lock (&data->lock);
|
||
should_return = g_atomic_int_compare_and_exchange (&data->will_return, NOT_YET, COMPLETED);
|
||
g_mutex_unlock (&data->lock);
|
||
|
||
if (should_return)
|
||
{
|
||
if (addresses != NULL)
|
||
g_task_return_pointer (task, g_steal_pointer (&addresses), (GDestroyNotify) g_resolver_free_addresses);
|
||
else
|
||
g_task_return_error (task, g_steal_pointer (&local_error));
|
||
}
|
||
|
||
g_clear_pointer (&addresses, g_resolver_free_addresses);
|
||
}
|
||
break;
|
||
case LOOKUP_BY_ADDRESS:
|
||
{
|
||
gchar *name = do_lookup_by_address (data->lookup_by_address.address,
|
||
cancellable,
|
||
&local_error);
|
||
|
||
g_mutex_lock (&data->lock);
|
||
should_return = g_atomic_int_compare_and_exchange (&data->will_return, NOT_YET, COMPLETED);
|
||
g_mutex_unlock (&data->lock);
|
||
|
||
if (should_return)
|
||
{
|
||
if (name != NULL)
|
||
g_task_return_pointer (task, g_steal_pointer (&name), g_free);
|
||
else
|
||
g_task_return_error (task, g_steal_pointer (&local_error));
|
||
}
|
||
|
||
g_clear_pointer (&name, g_free);
|
||
}
|
||
break;
|
||
case LOOKUP_RECORDS:
|
||
{
|
||
GList *records = do_lookup_records (data->lookup_records.rrname,
|
||
data->lookup_records.record_type,
|
||
cancellable,
|
||
&local_error);
|
||
|
||
g_mutex_lock (&data->lock);
|
||
should_return = g_atomic_int_compare_and_exchange (&data->will_return, NOT_YET, COMPLETED);
|
||
g_mutex_unlock (&data->lock);
|
||
|
||
if (should_return)
|
||
{
|
||
if (records != NULL)
|
||
g_task_return_pointer (task, g_steal_pointer (&records), (GDestroyNotify) free_records);
|
||
else
|
||
g_task_return_error (task, g_steal_pointer (&local_error));
|
||
}
|
||
|
||
g_clear_pointer (&records, free_records);
|
||
}
|
||
break;
|
||
default:
|
||
g_assert_not_reached ();
|
||
}
|
||
|
||
/* Signal completion of a task. */
|
||
g_mutex_lock (&data->lock);
|
||
data->has_returned = TRUE;
|
||
g_cond_broadcast (&data->cond);
|
||
g_mutex_unlock (&data->lock);
|
||
|
||
g_object_unref (task);
|
||
}
|
||
|
||
static void
|
||
g_threaded_resolver_class_init (GThreadedResolverClass *threaded_class)
|
||
{
|
||
GObjectClass *object_class = G_OBJECT_CLASS (threaded_class);
|
||
GResolverClass *resolver_class = G_RESOLVER_CLASS (threaded_class);
|
||
|
||
object_class->finalize = g_threaded_resolver_finalize;
|
||
|
||
resolver_class->lookup_by_name = lookup_by_name;
|
||
resolver_class->lookup_by_name_async = lookup_by_name_async;
|
||
resolver_class->lookup_by_name_finish = lookup_by_name_finish;
|
||
resolver_class->lookup_by_name_with_flags = lookup_by_name_with_flags;
|
||
resolver_class->lookup_by_name_with_flags_async = lookup_by_name_with_flags_async;
|
||
resolver_class->lookup_by_name_with_flags_finish = lookup_by_name_with_flags_finish;
|
||
resolver_class->lookup_by_address = lookup_by_address;
|
||
resolver_class->lookup_by_address_async = lookup_by_address_async;
|
||
resolver_class->lookup_by_address_finish = lookup_by_address_finish;
|
||
resolver_class->lookup_records = lookup_records;
|
||
resolver_class->lookup_records_async = lookup_records_async;
|
||
resolver_class->lookup_records_finish = lookup_records_finish;
|
||
}
|