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
|
/* -*-mode:c; c-style:k&r; c-basic-offset:4; -*- */
/* Balsa E-Mail Client
*
* Copyright (C) 2021 Albrecht Dreß <albrecht.dress@arcor.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <https://www.gnu.org/licenses/>.
*/
/*
* Filtering of external resources referenced in HTML messages
*
* The Webkit extension expects a user message "load_ext" from the main process indicating if external resources shall be loaded.
* If not, all images are redirected to a non-existing image, whilst other resources (e.g. fonts etc.) are simply ignored.
*/
#if defined(HAVE_CONFIG_H) && HAVE_CONFIG_H
# include "config.h"
#endif /* HAVE_CONFIG_H */
#ifdef HAVE_HTML_WIDGET
#if defined(GTK_DISABLE_DEPRECATED)
#define GtkAction GAction
#include <webkit2/webkit-web-extension.h>
#undef GtkAction
#else /* defined(GTK_DISABLE_DEPRECATED) */
#include <webkit2/webkit-web-extension.h>
#endif /* defined(GTK_DISABLE_DEPRECATED) */
#include <string.h>
#ifdef G_LOG_DOMAIN
# undef G_LOG_DOMAIN
#endif
#define G_LOG_DOMAIN "html"
#define LOAD_EXT_KEY "load-ext"
G_MODULE_EXPORT void webkit_web_extension_initialize(WebKitWebExtension *extension);
static gboolean
lbhf_chk_send_request(WebKitWebPage *web_page,
WebKitURIRequest *request,
WebKitURIResponse G_GNUC_UNUSED *redirected_response,
gpointer G_GNUC_UNUSED user_data)
{
const gchar *uri = webkit_uri_request_get_uri(request);
gboolean result; /* note: TRUE to skip this request, FALSE to process it */
result = (strcmp(uri, "about:blank") != 0) && (strncmp(uri, "cid:", 4UL) != 0);
if (result) {
gboolean *load_val;
load_val = g_object_get_data(G_OBJECT(web_page), LOAD_EXT_KEY);
if (load_val == NULL) {
g_warning("[HTML filter] %s: no policy for loading external resource %s", __func__, uri);
} else if (*load_val) {
g_debug("[HTML filter] %s: accept %s", __func__, uri);
result = FALSE;
} else {
webkit_uri_request_set_uri(request, "about:blank");
g_debug("[HTML filter] %s: request for uri %s blocked", __func__, uri);
result = FALSE;
}
}
return result;
}
static gboolean
lbhf_page_user_message_cb(WebKitWebPage *web_page,
WebKitUserMessage *message,
gpointer G_GNUC_UNUSED user_data)
{
gboolean result;
if (strcmp(webkit_user_message_get_name(message), "load_ext") == 0) {
GVariant *data;
gboolean *load_val;
data = webkit_user_message_get_parameters(message);
load_val = g_new(gboolean, 1U);
*load_val = g_variant_get_boolean(data);
g_debug("[HTML filter] %s: page %p: load externals = %d", __func__, web_page, *load_val);
g_object_set_data_full(G_OBJECT(web_page), LOAD_EXT_KEY, load_val, g_free);
result = TRUE;
} else {
g_debug("[HTML filter] %s: unexpected message '%s'", __func__, webkit_user_message_get_name(message));
result = FALSE;
}
return result;
}
static void
lbhf_page_created_callback(WebKitWebExtension G_GNUC_UNUSED *extension,
WebKitWebPage *web_page,
gpointer G_GNUC_UNUSED user_data)
{
g_debug("[HTML filter] %s: page %p created", __func__, web_page);
g_signal_connect(web_page, "user-message-received", G_CALLBACK(lbhf_page_user_message_cb), NULL);
g_signal_connect(web_page, "send-request", G_CALLBACK(lbhf_chk_send_request), NULL);
}
G_MODULE_EXPORT void
webkit_web_extension_initialize(WebKitWebExtension *extension)
{
static guint main_notified = 0U;
g_debug("[HTML filter] %s", __func__);
g_signal_connect(extension, "page-created", G_CALLBACK(lbhf_page_created_callback), NULL);
if (g_atomic_int_or(&main_notified, 1U) == 0U) {
WebKitUserMessage *message;
/* report the main Balsa process that the HTML filter extension has been found */
message = webkit_user_message_new("balsa-html-filter", NULL);
webkit_web_extension_send_message_to_context(extension, message, NULL, NULL, NULL);
}
}
#endif
|
