/*
* Copyright © 2017 Endless Mobile, Inc.
*
* SPDX-License-Identifier: LGPL-2.0+
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* 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.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Authors:
* - Philip Withnall <withnall@endlessm.com>
*/
#include "config.h"
#include <fcntl.h>
#include <gio/gio.h>
#include <glib.h>
#include <glib-object.h>
#include <libglnx.h>
#include "ostree-autocleanups.h"
#include "ostree-remote-private.h"
#include "ostree-repo.h"
#include "ostree-repo-private.h"
#include "ostree-repo-finder.h"
#include "ostree-repo-finder-override.h"
/**
* SECTION:ostree-repo-finder-override
* @title: OstreeRepoFinderOverride
* @short_description: Finds remote repositories from a list of repository URIs
* @stability: Unstable
* @include: libostree/ostree-repo-finder-override.h
*
* #OstreeRepoFinderOverride is an implementation of #OstreeRepoFinder which
* looks refs up in a list of remotes given by their URI, and returns the URIs
* which contain the refs. Duplicate remote URIs are combined into a single
* #OstreeRepoFinderResult which lists multiple refs.
*
* Each result is given an #OstreeRepoFinderResult.priority value of 20, which
* ranks its results above those from the other default #OstreeRepoFinder
* implementations.
*
* Results can only be returned for a ref if a remote and keyring are configured
* locally for the collection ID of that ref, otherwise there would be no keys
* available to verify signatures on commits for that ref.
*
* This is intended to be used for user-provided overrides and testing software
* which uses #OstreeRepoFinder. For production use, #OstreeRepoFinderConfig is
* recommended instead.
*
* Since: 2018.6
*/
static void ostree_repo_finder_override_iface_init (OstreeRepoFinderInterface *iface);
struct _OstreeRepoFinderOverride
{
GObject parent_instance;
GPtrArray *override_uris; /* (owned) (element-type utf8) */
};
G_DEFINE_TYPE_WITH_CODE (OstreeRepoFinderOverride, ostree_repo_finder_override, G_TYPE_OBJECT,
G_IMPLEMENT_INTERFACE (OSTREE_TYPE_REPO_FINDER, ostree_repo_finder_override_iface_init))
static gint
results_compare_cb (gconstpointer a,
gconstpointer b)
{
const OstreeRepoFinderResult *result_a = *((const OstreeRepoFinderResult **) a);
const OstreeRepoFinderResult *result_b = *((const OstreeRepoFinderResult **) b);
return ostree_repo_finder_result_compare (result_a, result_b);
}
/* This must return a valid remote name (suitable for use in a refspec). */
static gchar *
uri_and_keyring_to_name (const gchar *uri,
const gchar *keyring)
{
g_autofree gchar *escaped_uri = g_uri_escape_string (uri, NULL, FALSE);
g_autofree gchar *escaped_keyring = g_uri_escape_string (keyring, NULL, FALSE);
/* FIXME: Need a better separator than `_`, since it’s not escaped in the input. */
g_autofree gchar *out = g_strdup_printf ("%s_%s", escaped_uri, escaped_keyring);
for (gsize i = 0; out[i] != '\0'; i++)
{
if (out[i] == '%')
out[i] = '_';
}
g_return_val_if_fail (ostree_validate_remote_name (out, NULL), NULL);
return g_steal_pointer (&out);
}
/* Version of ostree_repo_remote_list_collection_refs() which takes an
* #OstreeRemote. */
static gboolean
repo_remote_list_collection_refs (OstreeRepo *repo,
const gchar *remote_uri,
GHashTable **out_all_refs,
GCancellable *cancellable,
GError **error)
{
g_autofree gchar *name = uri_and_keyring_to_name (remote_uri, "");
g_autoptr(OstreeRemote) remote = ostree_remote_new (name);
g_key_file_set_string (remote->options, remote->group, "url", remote_uri);
gboolean remote_already_existed = _ostree_repo_add_remote (repo, remote);
gboolean success = ostree_repo_remote_list_collection_refs (repo,
remote->name,
out_all_refs,
cancellable,
error);
if (!remote_already_existed)
_ostree_repo_remove_remote (repo, remote);
return success;
}
static void
ostree_repo_finder_override_resolve_async (OstreeRepoFinder *finder,
const OstreeCollectionRef * const *refs,
OstreeRepo *parent_repo,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
OstreeRepoFinderOverride *self = OSTREE_REPO_FINDER_OVERRIDE (finder);
g_autoptr(GTask) task = NULL;
g_autoptr(GPtrArray) results = NULL;
const gint priority = 20; /* arbitrarily chosen; higher priority than the others */
gsize i, j;
g_autoptr(GHashTable) repo_remote_to_refs = NULL; /* (element-type OstreeRemote GHashTable) */
GHashTable *supported_ref_to_checksum; /* (element-type OstreeCollectionRef utf8) */
GHashTableIter iter;
const gchar *remote_uri;
task = g_task_new (finder, cancellable, callback, user_data);
g_task_set_source_tag (task, ostree_repo_finder_override_resolve_async);
results = g_ptr_array_new_with_free_func ((GDestroyNotify) ostree_repo_finder_result_free);
repo_remote_to_refs = g_hash_table_new_full (g_direct_hash, g_direct_equal,
(GDestroyNotify) ostree_remote_unref,
(GDestroyNotify) g_hash_table_unref);
g_debug ("%s: Checking %u overrides", G_STRFUNC, self->override_uris->len);
for (i = 0; i < self->override_uris->len; i++)
{
g_autoptr(GError) local_error = NULL;
g_autoptr(GHashTable) remote_refs = NULL; /* (element-type OstreeCollectionRef utf8) */
const gchar *checksum;
gboolean resolved_a_ref = FALSE;
remote_uri = self->override_uris->pdata[i];
if (!repo_remote_list_collection_refs (parent_repo, remote_uri,
&remote_refs, cancellable,
&local_error))
{
g_debug ("Ignoring remote ‘%s’ due to error loading its refs: %s",
remote_uri, local_error->message);
g_clear_error (&local_error);
continue;
}
for (j = 0; refs[j] != NULL; j++)
{
g_autoptr(OstreeRemote) keyring_remote = NULL;
/* Look up the GPG keyring for this ref. */
keyring_remote = ostree_repo_resolve_keyring_for_collection (parent_repo,
refs[j]->collection_id,
cancellable, &local_error);
if (keyring_remote == NULL)
{
g_debug ("Ignoring ref (%s, %s) due to missing keyring: %s",
refs[j]->collection_id, refs[j]->ref_name, local_error->message);
g_clear_error (&local_error);
continue;
}
if (g_hash_table_lookup_extended (remote_refs, refs[j], NULL, (gpointer *) &checksum))
{
g_autoptr(OstreeRemote) remote = NULL;
/* The requested ref is listed in the refs for this remote. Add
* the remote to the results, and the ref to its
* @supported_ref_to_checksum. */
g_debug ("Resolved ref (%s, %s) to remote ‘%s’.",
refs[j]->collection_id, refs[j]->ref_name, remote_uri);
resolved_a_ref = TRUE;
/* Build an #OstreeRemote. Use the escaped URI, since remote->name
* is used in file paths, so needs to not contain special characters. */
g_autofree gchar *name = uri_and_keyring_to_name (remote_uri, keyring_remote->name);
remote = ostree_remote_new_dynamic (name, keyring_remote->name);
/* gpg-verify-summary is false since we use the unsigned summary file support. */
g_key_file_set_string (remote->options, remote->group, "url", remote_uri);
g_key_file_set_boolean (remote->options, remote->group, "gpg-verify", TRUE);
g_key_file_set_boolean (remote->options, remote->group, "gpg-verify-summary", FALSE);
supported_ref_to_checksum = g_hash_table_lookup (repo_remote_to_refs, remote);
if (supported_ref_to_checksum == NULL)
{
supported_ref_to_checksum = g_hash_table_new_full (ostree_collection_ref_hash,
ostree_collection_ref_equal,
NULL, g_free);
g_hash_table_insert (repo_remote_to_refs, ostree_remote_ref (remote), supported_ref_to_checksum /* transfer */);
}
g_hash_table_insert (supported_ref_to_checksum,
(gpointer) refs[j], g_strdup (checksum));
}
}
if (!resolved_a_ref)
g_debug ("Ignoring remote ‘%s’ due to it not advertising any of the requested refs.",
remote_uri);
}
/* Aggregate the results. */
g_hash_table_iter_init (&iter, repo_remote_to_refs);
OstreeRemote *remote;
while (g_hash_table_iter_next (&iter, (gpointer *) &remote, (gpointer *) &supported_ref_to_checksum))
g_ptr_array_add (results, ostree_repo_finder_result_new (remote, finder, priority, supported_ref_to_checksum, NULL, 0));
g_ptr_array_sort (results, results_compare_cb);
g_task_return_pointer (task, g_steal_pointer (&results), (GDestroyNotify) g_ptr_array_unref);
}
static GPtrArray *
ostree_repo_finder_override_resolve_finish (OstreeRepoFinder *finder,
GAsyncResult *result,
GError **error)
{
g_return_val_if_fail (g_task_is_valid (result, finder), NULL);
return g_task_propagate_pointer (G_TASK (result), error);
}
static void
ostree_repo_finder_override_init (OstreeRepoFinderOverride *self)
{
self->override_uris = g_ptr_array_new_with_free_func ((GDestroyNotify) g_free);
}
static void
ostree_repo_finder_override_finalize (GObject *object)
{
OstreeRepoFinderOverride *self = OSTREE_REPO_FINDER_OVERRIDE (object);
g_clear_pointer (&self->override_uris, g_ptr_array_unref);
G_OBJECT_CLASS (ostree_repo_finder_override_parent_class)->finalize (object);
}
static void
ostree_repo_finder_override_class_init (OstreeRepoFinderOverrideClass *klass)
{
GObjectClass *object_class = G_OBJECT_CLASS (klass);
object_class->finalize = ostree_repo_finder_override_finalize;
}
static void
ostree_repo_finder_override_iface_init (OstreeRepoFinderInterface *iface)
{
iface->resolve_async = ostree_repo_finder_override_resolve_async;
iface->resolve_finish = ostree_repo_finder_override_resolve_finish;
}
/**
* ostree_repo_finder_override_new:
*
* Create a new #OstreeRepoFinderOverride.
*
* Returns: (transfer full): a new #OstreeRepoFinderOverride
* Since: 2018.6
*/
OstreeRepoFinderOverride *
ostree_repo_finder_override_new (void)
{
return g_object_new (OSTREE_TYPE_REPO_FINDER_OVERRIDE, NULL);
}
/**
* ostree_repo_finder_override_add_uri:
* @uri: URI to add to the repo finder
*
* Add the given @uri to the set of URIs which the repo finder will search for
* matching refs when ostree_repo_finder_resolve_async() is called on it.
*
* Since: 2018.6
*/
void
ostree_repo_finder_override_add_uri (OstreeRepoFinderOverride *self,
const gchar *uri)
{
g_return_if_fail (OSTREE_IS_REPO_FINDER_OVERRIDE (self));
g_return_if_fail (uri != NULL);
g_ptr_array_add (self->override_uris, g_strdup (uri));
}