1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
|
/* vi:set et sw=2 sts=2 cin cino=t0,f0,(0,{s,>2s,n-s,^-s,e-s:
* Copyright © 2018 Endless Mobile, Inc.
*
* This program 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 2.1 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, see <http://www.gnu.org/licenses/>.
*
* Authors:
* Philip Withnall <withnall@endlessm.com>
*/
#include "config.h"
#include <glib.h>
#include <gio/gio.h>
#include <libmalcontent/app-filter.h>
#include "flatpak-parental-controls-private.h"
/*
* See https://www.freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-content_rating
* for details of the appstream content rating specification.
*
* See https://hughsie.github.io/oars/ for details of OARS. Specifically,
* https://github.com/hughsie/oars/tree/master/specification/.
*/
/* Convert an appstream <content_attribute/> value to #MctAppFilterOarsValue.
* https://www.freedesktop.org/software/appstream/docs/chap-Metadata.html#tag-content_rating
*/
static MctAppFilterOarsValue
app_filter_oars_value_from_appdata (const gchar *appdata_value)
{
g_return_val_if_fail (appdata_value != NULL, MCT_APP_FILTER_OARS_VALUE_UNKNOWN);
if (g_str_equal (appdata_value, "intense"))
return MCT_APP_FILTER_OARS_VALUE_INTENSE;
else if (g_str_equal (appdata_value, "moderate"))
return MCT_APP_FILTER_OARS_VALUE_MODERATE;
else if (g_str_equal (appdata_value, "mild"))
return MCT_APP_FILTER_OARS_VALUE_MILD;
else if (g_str_equal (appdata_value, "none"))
return MCT_APP_FILTER_OARS_VALUE_NONE;
else if (g_str_equal (appdata_value, "unknown"))
return MCT_APP_FILTER_OARS_VALUE_UNKNOWN;
else
return MCT_APP_FILTER_OARS_VALUE_UNKNOWN;
}
static const gchar *
app_filter_oars_value_to_string (MctAppFilterOarsValue oars_value)
{
switch (oars_value)
{
case MCT_APP_FILTER_OARS_VALUE_UNKNOWN: return "unknown";
case MCT_APP_FILTER_OARS_VALUE_INTENSE: return "intense";
case MCT_APP_FILTER_OARS_VALUE_MODERATE: return "moderate";
case MCT_APP_FILTER_OARS_VALUE_MILD: return "mild";
case MCT_APP_FILTER_OARS_VALUE_NONE: return "none";
default: return "unknown";
}
}
/**
* flatpak_oars_check_rating:
* @content_rating: (nullable) (transfer none): OARS ratings for the app,
* or %NULL if none are known
* @content_rating_type: (nullable): scheme used in @content_rating, such as
* `oars-1.0` or `oars-1.1`, or %NULL if @content_rating is %NULL
* @filter: user’s parental controls settings
*
* Check whether the OARS rating in @content_rating is as, or less, extreme than
* the user’s preferences in @filter. If so (i.e. if the app is suitable for
* this user to use), return %TRUE; otherwise return %FALSE.
*
* @content_rating may be %NULL if no OARS ratings are provided for the app. If
* so, we have to assume the most restrictive ratings.
*
* Returns: %TRUE if the app is safe to install, %FALSE otherwise
*/
gboolean
flatpak_oars_check_rating (GHashTable *content_rating,
const gchar *content_rating_type,
MctAppFilter *filter)
{
const gchar * const supported_rating_types[] = { "oars-1.0", "oars-1.1", NULL };
g_autofree const gchar **oars_sections = mct_app_filter_get_oars_sections (filter);
MctAppFilterOarsValue default_rating_value;
if (content_rating_type != NULL &&
!g_strv_contains (supported_rating_types, content_rating_type))
return FALSE;
/* If the app has a <content_rating/> element, even if it has no OARS sections
* in it, use a default value of `none` for any missing sections. Otherwise,
* if the app has no <content_rating/> element, use `unknown`. */
if (content_rating != NULL)
default_rating_value = MCT_APP_FILTER_OARS_VALUE_NONE;
else
default_rating_value = MCT_APP_FILTER_OARS_VALUE_UNKNOWN;
for (gsize i = 0; oars_sections[i] != NULL; i++)
{
MctAppFilterOarsValue rating_value;
MctAppFilterOarsValue filter_value = mct_app_filter_get_oars_value (filter,
oars_sections[i]);
const gchar *appdata_value = NULL;
if (content_rating != NULL)
appdata_value = g_hash_table_lookup (content_rating, oars_sections[i]);
if (appdata_value != NULL)
rating_value = app_filter_oars_value_from_appdata (appdata_value);
else
rating_value = default_rating_value;
if (filter_value < rating_value ||
(rating_value == MCT_APP_FILTER_OARS_VALUE_UNKNOWN &&
filter_value != MCT_APP_FILTER_OARS_VALUE_UNKNOWN) ||
(rating_value != MCT_APP_FILTER_OARS_VALUE_UNKNOWN &&
filter_value == MCT_APP_FILTER_OARS_VALUE_UNKNOWN))
{
g_info ("%s: Comparing rating ‘%s’: app has ‘%s’ but policy has ‘%s’ unknown: OARS check failed",
G_STRFUNC, oars_sections[i],
app_filter_oars_value_to_string (rating_value),
app_filter_oars_value_to_string (filter_value));
return FALSE;
}
}
return TRUE;
}
|
